Find $a$ if the point $(3,a)$ is on the line that passes through $(-2,7)$ and $(5,-3)$.
+9481 the slope between (-2, 7) and (5, -3) = [ -3 - 7 ] / [ 5 - -2 ] = -10/7
And since (3, a) lies on the same line as those two points, then we know.....
the slope between (3, a) and (-2, 7) = -10/7
[ 7 - a ] / [ -2 - 3 ] = -10/7
[ 7 - a ] / [ -5 ] = -10/7 Multiply both sides by -5 .
7 - a = 50/7 Subtract 7 from both sides.
-a = 50/7 - 7
-a = 50/7 - 49/7
-a = 1/7
a = -1/7 And here's a graph: https://www.desmos.com/calculator/prq2oggmcv
+9481 the slope between (-2, 7) and (5, -3) = [ -3 - 7 ] / [ 5 - -2 ] = -10/7
And since (3, a) lies on the same line as those two points, then we know.....
the slope between (3, a) and (-2, 7) = -10/7
[ 7 - a ] / [ -2 - 3 ] = -10/7
[ 7 - a ] / [ -5 ] = -10/7 Multiply both sides by -5 .
7 - a = 50/7 Subtract 7 from both sides.
-a = 50/7 - 7
-a = 50/7 - 49/7
-a = 1/7
a = -1/7 And here's a graph: https://www.desmos.com/calculator/prq2oggmcv
