Question

question
solve the system by substitution.

y = -2x - 7
9x - 10y = 12

answer attempt 1 out of 2
(\square, \square) submit answer

Explanation:

Step1: Substitute \( y = -2x - 7 \) into \( 9x - 10y = 12 \)

We replace \( y \) in the second equation with the expression from the first equation. So we get \( 9x - 10(-2x - 7) = 12 \).

Step2: Simplify the equation

First, distribute the -10: \( 9x + 20x + 70 = 12 \). Then combine like terms: \( 29x + 70 = 12 \). Subtract 70 from both sides: \( 29x = 12 - 70 \), which simplifies to \( 29x = -58 \).

Step3: Solve for \( x \)

Divide both sides by 29: \( x = \frac{-58}{29} = -2 \).

Step4: Solve for \( y \)

Substitute \( x = -2 \) into \( y = -2x - 7 \). So \( y = -2(-2) - 7 = 4 - 7 = -3 \).

Answer:

\((-2, -3)\)