So first you multiply 2 and 4x to get 8x. Then you multiply 2 and 5 to get 10. So the problem will look like:
8x+10=90
Then you subtract 10 on both sides of the problem to get:
8x=80
And then divide 8 on both sides to get
x=10
$0.79
x 3.7
---------
553
+2370
---------
2.923----> move the decimal three times to the left because that is how many spaces you have to the right on the actual equation until the next decimal.
The product of 0.79x 3.7 is 2.923. And, the decimal was moved three times to the right of the equation because of the number of spaces until the next decimal which then allows you to move the decimal three times to the left on the product.
T = 5.34 + 0.78m
T = 5.34 + 0.78 * 5
T = 5.34 + 3.9
T = 9.24
Tina was charged $9.24 at the car wash for 5 minutes.
she left her computer open for 48 hours