Atest has 20 question and is worth 100 points. the test consists of true or false questions worth 3 points each and multiple choice questions worth 11 points each. how many multiple choice questions are on the test?

10 or 15 that is what I think

X=number of true or false
y=number of multiplule choice

total questions is 20
x+y=20

total poits is 100
3x+11y=100

eliminate x's

multiply first equaiton by -3 and add to 2nd

-3x-3y=-60
3x+11y=100 +
0x+8y=40

8y=40
divide both sides by 8
y=5

5 multipule choice questions