16:64
5:x (Cross Multiply)
16x = 64*5
16x = 320 (Then Divide both sides by 16 to isolate x)
x= 20
Yes! Yup your right! Congrats yup!
Answer:
<h3>f =27</h3>
Step-by-step explanation:

Collect like terms and simplify

Switch sides

8x+15=7
In the statement the phrase the sum of can tell you that it is going to be an addition problem. So 8x ( eight times a number) would be added to the 15, 8x+15. Since its an addition problem the part where it says ' ... is seven', you know that it will all equal 7. So the answer would be 8x+15=7.