72.0k views
1 vote
Find y, 3y + 7y - 84 = 180

User Hao Ma
by
8.0k points

2 Answers

3 votes

Answer: y=26.4

Explanation:

First we need to simplify 3y+7y .... that would be 10y.

Now we have 10y-84=180. We can add 84 to both sides of the equation

So now we have 10y= 180+84 = 10y= 264

Divide both sides by 10= y= 26.4

Now we can check this answer by inputting 26.4 to all the y values in the equation.

(3*26.4) +(7*26.4) - 84=180

79.2 + 184.8 -84=180

180=180 so we know 26.4 is the correct answer

User Bossk
by
8.3k points
1 vote

Answer:

26.4

Explanation:

You can add Y together because they have the same variable making it 10y

The equation is now 10y - 84 = 180

Add 84 to 180 since on the left side it was -84 (Imagine it crossed a magic bridge and become the opposite of what it is)

The equation is now 10y = 264

Divide the equation by 10 because 10 crossed a "magic bridge" to the other side and became division instead of multiplication

The equation is now solved = 26.4

We can cross check this by adding it to the first equation

3(26.4) + 7(26.4) - 84

which gives us 180

Hope this helps

User Mummybot
by
7.5k points

No related questions found

Welcome to QAmmunity.org, where you can ask questions and receive answers from other members of our community.