Respuesta :
You need to solve for one variable in equation 1 and substitute it in equation 2 to solve.
Equation 1: x+y=24
x= number of 3 pt questions
y= number of 5 pt questions
24= Total number of questions
Equation 2: 3x+5y=100
100= Total point value possible on test
3x= point value of 3 pt questions
5y= point value of 5 pt questions
x+y=24
Subtract y from both sides
x=24-y
Substitute in equation 2:
3x+5y=100
3(24-y) +5y=100
72-3y+5y=100
72+2y=100
Subtract 72 from both sides
2y=28
Divide both sides by 2
y=14
Substitute y=14 back in to solve for x:
3x+5y=100
3x+5(14)=100
3x+70=100
Subtract 70 from both sides
3x=30
Divide both sides by 3
x=10
So there are 10 three point questions
There are 14 five point questions.
Hope this helped! :)
Equation 1: x+y=24
x= number of 3 pt questions
y= number of 5 pt questions
24= Total number of questions
Equation 2: 3x+5y=100
100= Total point value possible on test
3x= point value of 3 pt questions
5y= point value of 5 pt questions
x+y=24
Subtract y from both sides
x=24-y
Substitute in equation 2:
3x+5y=100
3(24-y) +5y=100
72-3y+5y=100
72+2y=100
Subtract 72 from both sides
2y=28
Divide both sides by 2
y=14
Substitute y=14 back in to solve for x:
3x+5y=100
3x+5(14)=100
3x+70=100
Subtract 70 from both sides
3x=30
Divide both sides by 3
x=10
So there are 10 three point questions
There are 14 five point questions.
Hope this helped! :)