8 students made 4 mistakes or more
 
        
             
        
        
        
First, find the x-intercept.
The x-intercept will be at the point (x, 0) where x is any real number. If we substitute the x-coordinate and the y-coordinate for the x and y variables in the equation, we can solve for x.
5y + 3x = 15
5(0) + 3x = 15
3x + 15
x = 5
We found the x-intercept now find the y-intercept with the same process.
The y-intercept will be at the point (0, y) where y is any real number.
5y + 3x = 15
5y + 3(0) = 15
5y = 15
y = 3
So, the x-intercept is (5, 0) and the y-intercept is (0, 3)
        
             
        
        
        
Answer:
1.) subtract = 1 1/3 - 3 1/2 = answer 
2.) subtract = 6 3/4 - 1 1/2 = answer 
3.) add = 3 1/4 + 2 1/8= answer 
4.) subtract = 4 3/4 - 2 1/6 = answer
Step-by-step explanation:
5.) 3 lawns = 6 3/4 hrs
1st lawn 2 1/2 hrs
2nd lawn 1 3/4 hrs 
add 2 1/2  + 1 3/4 = total 
then 6 3/4 hrs - total = the amount it takes to mow the 3rd lawn 
im sure u know how to add and subtract fractions is u r in middle school :)
 
        
             
        
        
        
Use elimination method - I am eliminaing the y-variable.
1(5x + 8y = 16)    →    5x + 8y = 16
4(6x  - 2y = 54)    →  24x - 8y = 216
         Add equations: 29x       = 232
            Divide by 29:    x        = 8
Answer: x = 8