Question

The parametric equations x=t+4, y=2t+7 describe most closely which line?

A) y=2x
B) y=2x+1
C) y=x-1
D) y=2x-1

Answer 1

The parametric equations are describing the line "y = 2x -1" letter D.

Explanation:

In order to know which line it describes we need to replace the value for t from the first equation on the second one. To that we first need to isolate the "t" variable:

x = t + 4

x - 4 = t

t = x - 4

Using that in the second equation:

y = 2*(x - 4) + 7

y = 2*x - 8 + 7

y = 2*x - 1

The parametric equations are describing the line "y = 2x -1" letter D.