8th Grade Algebra
posted by Jaida .
1) An exam will have 20 questions worth a total of 100 points. There will be TrueFalse questions worth 3 points each and short essay questions worth 11 points each. Several students ask how many essay questions there will be, but the teacher won't tell. How many essay questions will there be.

let x = number of truefalse questions
let y = number of essay questions
x + y = 20
3x + 11 y = 100
Solve those two equations. I assume you know how. Substitution is one way. 
I got 15 TF Questions
and 5 Essay Questions.
is that right ?? 
check: 45 + 55 = 100
Looks good! 
Thank You very mcuh.
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