To use elimination, you want the coefficients of one variable to be opposite*
Multiply both equations to get one of the variable's coefficients' Least Common Multiple! (Same idea as a least common denominator)
Ex. Solve
3x+5y=76
4x-3y=-5
Least Common Multiple:
4(3x+5y=76)----->12x+20y=304
-3(4x-3y=-5)------>-12x+9y=15
^^ you must have one negative so it can cancel out...for example, the 12.
29y=319
divide by 29 on both sides
y=11
plug the 11 into the y in the easier equation.
3x+5(11)=76
3x+55=76
subtract 55 on both sides
3x=21
- To use elimination, you want the coefficients of one variable to be opposite*
Multiply both equations to get one of the variable's coefficients' Least Common Multiple! (Same idea as a least common denominator)Ex. Solve
3x+5y=76
4x-3y=-5
Least Common Multiple:
4(3x+5y=76)----->12x+20y=304
-3(4x-3y=-5)------>-12x+9y=15
^^ you must have one negative so it can cancel out...for example, the 12.
29y=319
divide by 29 on both sides
y=11
plug the 11 into the y in the easier equation.
3x+5(11)=76
3x+55=76
subtract 55 on both sides
3x=21
divide by 3 on both sides
x=7
FINAL ANSWER - (7, 11)
-Jaryn Pitkowsky