On a test Eddie solved the equation $$\frac{5}{x-2} - \frac{20}{x^2 -4}=1$$ and found that x = 2 and x = 3. His steps were correct, so why was this answer marked wrong?
QUESTION 7. In an elementary school classroom, two students are given the task of cleaning the chalkboard. The first student can clean it by himself in one minute, while the other student takes 20 seconds longer. Which of the following equations can be used to determine how many seconds it would take for both students to clean the chalkboard if they work together?
QUESTION 8. Two rectangles are placed inside the other as shown in the figure below. If the ratio of the shaded area to the white area is I. what is the value of x?

1.) answer is 3 since if you plug it in, it will be 1/3

2.) 0 nothing makes it true.

4) x=3! If you plug in the numbers, it becomes 1/3+0/3=1/3
Working on 5!

is for questions 4 and 5

for the Eddie question, 3 is right but 2 is not because it would make it an undefined fraction. So x=3 is correct, but x=2 is extraneous.

I’m having a bit of trouble on five, sorry :( but i can still help for 7 and 8

7: 1/1+1/20=1/x I think. tell me if I’m wrong

8: 2.5, because 6 times 2.5 is 15, and that is 1/4 of 60.

RELATED: