# How do you solve the following system?: # 7x +5y =-15 , -4x -9y = 5#

##### 1 Answer

Oct 16, 2016

#### Explanation:

There is no single variable, so using the method of substitution will lead to some uncomfortable math.

Let's use the elimination method.

Make additive inverses. I have chosen the x terms for this.

Substitute

Substituting for x and y in B gives 5.

Despite the awkward fractions, the method remains the same.