jose has an upcoming world history exam that is worth 145 points and has 50 questions. Some of the questions are worth 2 points and some are worth 5 points

Question

How many 2 points questions are on the test?

How many 5 point questions are on the test?

X represents number of 2 points questions 

Y represents number of 5 points questions 

(make an equation for number of points and for total number of questions)

Answer 1

x + y = 50

2x + 5y = 145

 

These are your two equations above.

We can use elimination or substitution to

solve the system.

From 1st equation, y = 50-x

Substitute into 2nd equation.

 

2x + 5(50-x) = 145

2x + 250 - 5x = 145

-3x = 145-250

-3x = -105

x = 35 of the 2 point questions

 

So how many 5 point questins are there 

given that x+y = 50?