If -8x-9y=2 and -7x-6y=6 are true equations, what would be the value of -15 x-15 y ? Answer:

Set up equations: We have two equations: 1. -8x - 9y = 2 2. -7x - 6y = 6 We need to find the value of -15x - 15y. First, let's try to express -15x - 15y in terms of one of the given equations by finding a common factor.Find common factor: Looking at the coefficients of x in both equations, we can multiply the first equation by 7 and the second equation by 8 to get the coefficient of x in both equations to be -56x. So, we have: 7(-8x - 9y) = 7(2) 8(-7x - 6y) = 8(6)Multiply equations: Perform the multiplication for both equations: -56x - 63y = 14 -56x - 48y = 48 Now we have two new equations with the same coefficient for x.Subtract equations: We can now subtract the second new equation from the first new equation to eliminate x and find a relationship between y and the constants: (-56x - 63y) - (-56x - 48y) = 14 - 48Simplify y value: Simplify the subtraction: -56x + 56x - 63y + 48y = 14 - 48 -15y = -34 Now we have an equation with only y.Find x value: To find the value of y, we divide both sides of the equation by -15: y = -34 / -15 y = 34/15 We have found the value of y.Calculate final result: Now we need to find the value of x using one of the original equations. Let's use the first equation: -8x - 9y = 2 Substitute the value of y into the equation: -8x - 9(34/15) = 2Multiply 9 by 34/15: -8x - (306/15) = 2 Simplify the fraction: -8x - 20.4 = 2Add 20.4 to both sides to solve for x: -8x = 2 + 20.4 -8x = 22.4Divide both sides by -8 to find the value of x: x = 22.4 / -8 x = -2.8 We have found the value of x.Now we can find the value of -15x - 15y using the values of x and y we found: -15(-2.8) - 15(34/15)Perform the multiplication: 42 + (-34)Add the numbers to get the final value: 42 - 34 = 8 So, the value of -15x - 15y is 8.

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If
-8x-9y=2 and
-7x-6y=6 are true equations, what would be the value of
-15 x-15 y ?
Answer:

If $-\mathbf{8 x}-\mathbf{9 y}=\mathbf{2}$ and $-\mathbf{7 x}-6 \mathbf{y}=6$ are true equations, what would be the value of $-15 x-15 y$ ? $\newline$ Answer:

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Grade 8

Describe the graph of a linear equation

Full solution

Q. If

-\mathbf{8 x}-\mathbf{9 y}=\mathbf{2}

and

-\mathbf{7 x}-6 \mathbf{y}=6

are true equations, what would be the value of

-15 x-15 y

\newline

Answer:

Set up equations: We have two equations: $\newline$ $1$ . $-8x - 9y = 2$ $\newline$ $2$ . $-7x - 6y = 6$ $\newline$ We need to find the value of $-15x - 15y$ . $\newline$ First, let's try to express $-15x - 15y$ in terms of one of the given equations by finding a common factor.
Find common factor: Looking at the coefficients of $x$ in both equations, we can multiply the first equation by $7$ and the second equation by $8$ to get the coefficient of $x$ in both equations to be $-56x$ . $\newline$ So, we have: $\newline$ $7(-8x - 9y) = 7(2)$ $\newline$ $8(-7x - 6y) = 8(6)$
Multiply equations: Perform the multiplication for both equations: $\newline$ $-56x - 63y = 14$ $\newline$ $-56x - 48y = 48$ $\newline$ Now we have two new equations with the same coefficient for $x$ .
Subtract equations: We can now subtract the second new equation from the first new equation to eliminate $x$ and find a relationship between $y$ and the constants: $(-56x - 63y) - (-56x - 48y) = 14 - 48$
Simplify $y$ value: Simplify the subtraction: $\newline$ $-56x + 56x - 63y + 48y = 14 - 48$ $\newline$ $-15y = -34$ $\newline$ Now we have an equation with only $y$ .
Find x value: To find the value of y, we divide both sides of the equation by $-15$ : $\newline$ y = $-34 / -15$ $\newline$ y = $34/15$ $\newline$ We have found the value of y.
Calculate final result: Now we need to find the value of $x$ using one of the original equations. Let's use the first equation: $\newline$ $-8x - 9y = 2$ $\newline$ Substitute the value of $y$ into the equation: $\newline$ $-8x - 9(\frac{34}{15}) = 2$
Calculate final result: Now we need to find the value of $x$ using one of the original equations. Let's use the first equation: $\newline$ $-8x - 9y = 2$ $\newline$ Substitute the value of $y$ into the equation: $\newline$ $-8x - 9(\frac{34}{15}) = 2$ Multiply $9$ by $\frac{34}{15}$ : $\newline$ $-8x - (\frac{306}{15}) = 2$ $\newline$ Simplify the fraction: $\newline$ $-8x - 20.4 = 2$
Calculate final result: Now we need to find the value of $x$ using one of the original equations. Let's use the first equation: $\newline$ $-8x - 9y = 2$ $\newline$ Substitute the value of $y$ into the equation: $\newline$ $-8x - 9(\frac{34}{15}) = 2$ Multiply $9$ by $\frac{34}{15}$ : $\newline$ $-8x - (\frac{306}{15}) = 2$ $\newline$ Simplify the fraction: $\newline$ $-8x - 20.4 = 2$ Add $20.4$ to both sides to solve for $x$ : $\newline$ $-8x - 9y = 2$ $0$ $\newline$ $-8x - 9y = 2$ $1$
Calculate final result: Now we need to find the value of $x$ using one of the original equations. Let's use the first equation: $\newline$ $-8x - 9y = 2$ $\newline$ Substitute the value of $y$ into the equation: $\newline$ $-8x - 9(\frac{34}{15}) = 2$ Multiply $9$ by $\frac{34}{15}$ : $\newline$ $-8x - (\frac{306}{15}) = 2$ $\newline$ Simplify the fraction: $\newline$ $-8x - 20.4 = 2$ Add $20.4$ to both sides to solve for $x$ : $\newline$ $-8x - 9y = 2$ $0$ $\newline$ $-8x - 9y = 2$ $1$ Divide both sides by $-8x - 9y = 2$ $2$ to find the value of $x$ : $\newline$ $-8x - 9y = 2$ $4$ $\newline$ $-8x - 9y = 2$ $5$ $\newline$ We have found the value of $x$ .
Calculate final result: Now we need to find the value of $x$ using one of the original equations. Let's use the first equation: $\newline$ $-8x - 9y = 2$ $\newline$ Substitute the value of $y$ into the equation: $\newline$ $-8x - 9(\frac{34}{15}) = 2$ Multiply $9$ by $\frac{34}{15}$ : $\newline$ $-8x - (\frac{306}{15}) = 2$ $\newline$ Simplify the fraction: $\newline$ $-8x - 20.4 = 2$ Add $20.4$ to both sides to solve for $x$ : $\newline$ $-8x - 9y = 2$ $0$ $\newline$ $-8x - 9y = 2$ $1$ Divide both sides by $-8x - 9y = 2$ $2$ to find the value of $x$ : $\newline$ $-8x - 9y = 2$ $4$ $\newline$ $-8x - 9y = 2$ $5$ $\newline$ We have found the value of $x$ .Now we can find the value of $-8x - 9y = 2$ $7$ using the values of $x$ and $y$ we found: $\newline$ $y$ $0$
Calculate final result: Now we need to find the value of $x$ using one of the original equations. Let's use the first equation: $\newline$ $-8x - 9y = 2$ $\newline$ Substitute the value of $y$ into the equation: $\newline$ $-8x - 9(\frac{34}{15}) = 2$ Multiply $9$ by $\frac{34}{15}$ : $\newline$ $-8x - (\frac{306}{15}) = 2$ $\newline$ Simplify the fraction: $\newline$ $-8x - 20.4 = 2$ Add $20.4$ to both sides to solve for $x$ : $\newline$ $-8x - 9y = 2$ $0$ $\newline$ $-8x - 9y = 2$ $1$ Divide both sides by $-8x - 9y = 2$ $2$ to find the value of $x$ : $\newline$ $-8x - 9y = 2$ $4$ $\newline$ $-8x - 9y = 2$ $5$ $\newline$ We have found the value of $x$ .Now we can find the value of $-8x - 9y = 2$ $7$ using the values of $x$ and $y$ we found: $\newline$ $y$ $0$ Perform the multiplication: $\newline$ $y$ $1$
Calculate final result: Now we need to find the value of $x$ using one of the original equations. Let's use the first equation: $\newline$ $-8x - 9y = 2$ $\newline$ Substitute the value of $y$ into the equation: $\newline$ $-8x - 9(\frac{34}{15}) = 2$ Multiply $9$ by $\frac{34}{15}$ : $\newline$ $-8x - (\frac{306}{15}) = 2$ $\newline$ Simplify the fraction: $\newline$ $-8x - 20.4 = 2$ Add $20.4$ to both sides to solve for $x$ : $\newline$ $-8x - 9y = 2$ $0$ $\newline$ $-8x - 9y = 2$ $1$ Divide both sides by $-8x - 9y = 2$ $2$ to find the value of $x$ : $\newline$ $-8x - 9y = 2$ $4$ $\newline$ $-8x - 9y = 2$ $5$ $\newline$ We have found the value of $x$ . Now we can find the value of $-8x - 9y = 2$ $7$ using the values of $x$ and $y$ we found: $\newline$ $y$ $0$ Perform the multiplication: $\newline$ $y$ $1$ Add the numbers to get the final value: $\newline$ $y$ $2$ $\newline$ So, the value of $-8x - 9y = 2$ $7$ is $y$ $4$ .

If $-\mathbf{8 x}-\mathbf{9 y}=\mathbf{2}$ and $-\mathbf{7 x}-6 \mathbf{y}=6$ are true equations, what would be the value of $-15 x-15 y$ ? $\newline$ Answer:

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If −8x−9y=2 -\mathbf{8 x}-\mathbf{9 y}=\mathbf{2} −8x−9y=2 and −7x−6y=6 -\mathbf{7 x}-6 \mathbf{y}=6 −7x−6y=6 are true equations, what would be the value of −15x−15y -15 x-15 y −15x−15y ?\newlineAnswer:

If $-\mathbf{8 x}-\mathbf{9 y}=\mathbf{2}$ and $-\mathbf{7 x}-6 \mathbf{y}=6$ are true equations, what would be the value of $-15 x-15 y$ ? $\newline$ Answer: