Just multiply 37.7 by 4 and get your answer.
To solve for x just isolate x by moving the other variables so....:
First add c to both sides
g+c= y+x
Subtract y from both sides
g+c-y= x
That should be your final answer (we cannot come up with an actual digit for x because there are no numbers in this equation we simply can make an equation for x)
No she doesn't have enough money. All you do is multiply 8.60 by .2 which come out to 1.72 and 8.60 plus 1.73 which equals 10.33 so she needs 33 more cents tone able to tip 20%.
