What is the answer to this promblem

9514 1404 393

Step-by-step explanation:

Pick the variable you want to eliminate. Determine the coefficients of that variable in the two equations. Negate one of them. Multiply each equation by the coefficient that came from the other equation.

__

To eliminate x

The x-coefficients are 4 and 3. If we negate 4, then the resulting y-coefficient will be positive. We choose to multiply the first equation by 3, the second by -4.

Here is the result of adding those:

  3(4x +5y) -4(3x -2y) = 3(7) -4(-12)   ⇒   23y = 69

To eliminate y

The y-coefficients are 5 and -2. If we negate -2, then the resulting x-coefficient will be positive. We choose to multiply the first equation by 2 and the second by 5.

Here is the result of adding those:

  2(4x +5y) +5(3x -2y) = 2(7) +5(-12)   ⇒   23x = -46