Answer:
You're on the right track! You've correctly set up a system of equations based on the given information.
Now, let's solve this system of equations to find the values of x and y.
Here's the system of equations you have:
1. x + y = 35 (total number of problems)
2. 2x + 4y = 100 (total points on the test)
Let's use the first equation (x + y = 35) to express x in terms of y:
x = 35 - y
Now, substitute this expression for x into the second equation (2x + 4y = 100):
2(35 - y) + 4y = 100
Now, distribute and simplify:
70 - 2y + 4y = 100
Combine like terms:
2y = 100 - 70
2y = 30
Now, divide by 2 to solve for y:
y = 30 / 2
y = 15
So, you've found that y, the number of questions worth 4 points, is 15.
Now, you can use this value to find x, the number of questions worth 2 points, using the first equation:
x + 15 = 35
Subtract 15 from both sides:
x = 35 - 15
x = 20
So, you've found that x, the number of questions worth 2 points, is 20.
Therefore, there are 20 questions worth 2 points and 15 questions worth 4 points on the test.