Chapter 1 Section 4ab tutorial


♠How to rewrite equations with more than one variable
2x+5y=4
get y by itself...
5y= -2x=4 ab ^{Subtract 2x on both sides}
ab ^{Divide both sides by 5}

♠How to solve equations with more than one variable.
2x+5y=4
5y= -2x+4
ab^{Plug this equation into y in the original equation}


2x-2x+4=4ab^Distribute
0+4=4
x=0ac^{Input the 0 into y= equation}

ac^{Input 0 in xvariable's place}





♠Practice Problems
1) 4x+8y=12
2) x+2y=6
3) 17x+y=21
4) 0.5x+y=14