Section+7.2+-+Solving+Systems+by+Substitution

Review: find y if x=2 in 3y+2x=4. 3y+ 2(2)=4 3y+4=4 //.....-4 -4// y=0
 * __Section 7-2 Solving Systems with Substitutions__**

__Solving Systems with Substitution__ 1. Get one equation with a variable by itself. 2. Plug that equation (from step 1) into the other equation. 3. Solve 4. Substitute to get the other variable.   Ex. Solve the system: y=3x-2 ......................................2x+3y=5 Plug the top equation into the bottom equation.

2x+ 3(3x-2)=5 2x+ 9x-6=5 11x-6=5 11x=11 x=1 .... Now go plug x in to figure out what y is.

y=3(1)-2 y=3-2 y=1 Final solution is (1,1)... always write your solution as an ordered pair!!