Question

Please help!

Given the system of equations.

Which of the options represents the resulting equation after an equivalent expression for y is substituted into the second equation. (See Picture.)

A) 2x - (4x + 3) = 12
B) -4x + 4x - 3 = 3
C) 2 (4x + 3) - y
D) -4(4y + ) + y = 3

Answer 1

By using method of substitution we need to solve one equation for a variable and plug in that equation in the second equation.

Let's solve the first equation for y of the given system of equation.

So, -4x+y=3

4x-4x+y=4x+3 Add 4x to each sides of the equation.

y= 4x+3.

Next step is to plug in 4x+3 for y in the second equation. Hence, after substituting we will get:

2x-(4x+3)=12.

Hence the correct choice is A) 2x - (4x + 3) = 12.