Answer:
C
Step-by-step explanation:
To solve, use inverse operations:

Now we solve for both +/- 7.
x+6=7
x=1
x+6=-7
x=-13
Answer
40.9
Step-by-step explanation:
Answer:
24 blocks will be needed to make the tower that is 4 feet high
Step-by-step explanation:
Let us use the ratio method to solve the question
∵ Charlie knows that 3 blocks are needed to make a tower that is
0.5 foot high
∵ He needs to make a tower that is 4 feet high
→ By using the ratio method
→ Blocks : height (ft)
→ 3 : 0.5
→ x : 4
→ By using the cross multiplication
∵ x × 0.5 = 3 × 4
∴ 0.5x = 12
→ Divide both sides by 0.5 to find x
∵
= 
∴ x = 24
∵ x represents the number of blocks
∴ 24 blocks will be needed to make the tower that is 4 feet high