The graph of a line in the xy-plane passes through the points (2,3) and (4,6). The graph of a second line has a slope of 6 and contains the point (1,15). If the two lines intersect at the point (a,b), what is the value of ab ?Choose 1 answer:(A) −6(B) 6(C) 15(D) 24
Q. The graph of a line in the xy-plane passes through the points (2,3) and (4,6). The graph of a second line has a slope of 6 and contains the point (1,15). If the two lines intersect at the point (a,b), what is the value of ab ?Choose 1 answer:(A) −6(B) 6(C) 15(D) 24
Find Slope: First, find the slope of the line passing through the points (2,3) and (4,6).Slope (m)=(x2−x1)(y2−y1)=(4−2)(6−3)=23
Write Equation: Next, use the point-slope form to write the equation of the first line.y−y1=m(x−x1), where m is the slope and (x1,y1) is a point on the line.Using the point (2,3) and the slope 23, the equation becomes:y−3=(23)(x−2)
Simplify Equation: Simplify the equation of the first line to get it in slope-intercept formy=mx+b.y−3=(23)x−3y=(23)x
Write Second Line: Now, write the equation of the second line using its slope and the given point (1,15). The slope is 6, and using the point-slope form: y−y1=m(x−x1)y−15=6(x−1)
Simplify Second Line: Simplify the equation of the second line to get it in slope-intercept form.y−15=6x−6y=6x+9
Find Intersection Point: To find the intersection point(a,b), set the y-values of the two equations equal to each other since they both equal y at the point of intersection.(23)x=6x+9
Solve for x: Solve for x by getting all terms involving x on one side and constants on the other.23x−6x=9Multiply all terms by 2 to clear the fraction:3x−12x=18
Combine Like Terms: Combine like terms to solve for x.−9x=18x=−918x=−2
Find y-coordinate: Now that we have the x-coordinate of the intersection point, we can find the y-coordinate by plugging x into one of the line equations. We'll use the first line's equation.y=(23)xy=(23)(−2)y=−3
Intersection Point: The intersection point (a,b) is (−2,−3). To find the value of ab, multiply a and b together.ab=(−2)(−3)ab=6
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