The graph of a line in the xy-plane has a slope of 4 and contains the point (1,−5). The graph of a second line passes through the points (0,4) and (12,0). If the two lines intersect at the point (a,b), what is the value of a−b ?Choose 1 answer:(A) −9(B) −5(C) 0(D) 4
Q. The graph of a line in the xy-plane has a slope of 4 and contains the point (1,−5). The graph of a second line passes through the points (0,4) and (12,0). If the two lines intersect at the point (a,b), what is the value of a−b ?Choose 1 answer:(A) −9(B) −5(C) 0(D) 4
Find First Line Equation: First, let's find the equation of the first line with a slope of 4 that contains the point (1,−5). Using the point-slope form of a line equation: y−y1=m(x−x1), where m is the slope and (x1,y1) is the point on the line. y−(−5)=4(x−1)
Simplify First Line Equation: Simplify the equation of the first line:y+5=4x−4y=4x−4−5y=4x−9This is the equation of the first line.
Find Second Line Equation: Now, let's find the equation of the second line that passes through the points (0,4) and (12,0). We can use the slope formula: m=x2−x1y2−y1m=12−00−4m=12−4m=−31
Calculate Intersection Point Slope: Using the point-slope form again for the second line with the point (0,4):y−4=(−31)(x−0)y−4=(−31)xy=(−31)x+4This is the equation of the second line.
Find Intersection Point: To find the intersection point (a,b), we set the equations of the two lines equal to each other:4x−9=(−31)x+4
Calculate x-coordinate: Solve for x: 4x+(31)x=4+9(312)x+(31)x=13(313)x=13x=(313)13x=13×(133)x=3
Calculate y-coordinate: Now that we have the x-coordinate of the intersection point, we can find the y-coordinate by plugging x=3 into one of the line equations. Let's use the first line's equation:y=4x−9y=4(3)−9y=12−9y=3
Determine Intersection Point: We have found the intersection point (a,b) to be (3,3). Now we can find a−b: a−b=3−3a−b=0
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