Big Ideas Math Integrated I, 2016
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Big Ideas Math Integrated I, 2016 View details
1-4. Quiz
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Exercise 11 Page 242

If either of the variable terms would cancel out the corresponding variable term in the other equation, you can use the Elimination Method to solve the system.

(2,2)

Practice makes perfect
Since neither equation has a variable with a coefficient of 1, the Substitution Method may not be the easiest. Instead, let's use the Elimination Method. To use this method, one of the variable terms needs to be eliminated when one equation is added to or subtracted from the other equation. This means that either the x-terms or the y-terms must cancel each other out. 6 x+2 y=16 & (I) 2 x- y=2 & (II) Currently, none of the terms in this system will cancel out. Therefore, we need to find a common multiple between two variable like terms in the system. If we multiply (II) by 2, the y-terms will have opposite coefficients. 6 x+2 y=16 2(2 x- y)=2(2) ⇒ 6 x+ 2y=16 4 x- 2y=4We can see that the y-terms will eliminate each other if we add (I) to (II).
6x+2y=16 4x-2y=4
6x+2y=16 4x-2y+ 6x+2y=4+ 16
6x+2y=16 10x=20
6x+2y=16 x=2
Now we can solve for y by substituting the value of x into either equation and simplifying.
6x+2y=16 x=2
6( 2)+2y=16 x=2
12+2y=16 x=2
2y=4 x=2
y=2 x=2
The solution, or intersection point, of the system of equations is (2,2).