Question

which of the following equations corresponds to the diagram?
diagram with four rectangles labeled y + 7, total 78
answer
○ 4y + 7 = 78
○ 4 = 78(y + 7)
○ y + 7 = 19.5
○ 7 = 78y

Explanation:

Step1: Analyze the diagram

The diagram shows 4 equal parts each of value \(y + 7\), and the total is 78.

Step2: Set up the equation

Since there are 4 parts of \(y+7\) and the sum is 78, we use the formula \(4\times(\text{one - part})=\text{total}\). So, \(4(y + 7)=78\). Dividing both sides of \(4(y + 7)=78\) by 4 gives \(y + 7=\frac{78}{4}=19.5\).

Answer:

\(y + 7=19.5\)