Question

solve the following system of equations.express your answer as an ordered pair in the format (a,b) with no spaces the number or symbols 2x+5y=16 -5x-2y=2

Answer 1

The solution is (-2,4)

Explanation:

We'll solve the system

2x+5y=16

-5x-2y=2

using elimination by addition and subtraction.

Let's eliminate x first. To do this, multiply the first equation by 5 and multiply the second equation by 2. We get:

10x + 25y = 80

-10x - 4y = 4

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21y = 84. Thus, y = 84/21 = 4.

Subbing 4 for y in the second equation, we get

-5x -2(4) = 2, or

-8 - 2 = 5x, or

-10 = 5x. Thus, x = -10/5 = -2.

The solution is (-2,4)