Answer:
He was supposed to cross multiply the equation in the original equation. Step 2 was a wrong expression
Explanations:
The given equation is:
Cross multiply the equation, the equation becomes:
x = 8 - 12
x = -4
His mistake was in step 2, he did not properly expand the equation
The proper step was to cross multiply in step 2
Answer:
There are 60 marbles in the bag
Step-by-step explanation:
The total number of marbles times the probability of red marbles = number of red marbles
total * 7/10 = 42
Multiply each side by 10/7
total * 7/10 * 10/7 = 42*10/7
total
60
There are 60 marbles in the bag
Step-by-step explanation:
When you reflect a point across the line y = x, the x-coordinate and y-coordinate change places. If you reflect over the line y = -x, the x-coordinate and y-coordinate change places and are negated (the signs are changed). the line y = x is the point (y, x).