HELP ME PLZ WITH NUMBER 4

4 2/3 cups of water

Step-by-step explanation:

The original recipe has 3 1/2 cups of potatoes and 3 1/4 cups of water.

4.

If you put 5 cups of potatoes, you can find the amount of water you need using a proportion.

3 1/2 cups of potatoes is to 3 1/4 cups of water as 5 cups of of potatoes is to x cups of water.

(3 1/2) / (3 1/4) = 5/x

(7/2) / (13/4) = 5/x

7/2 * x = 13/4 * 5

2/7 * 7/2 * x = 2/7 * 13/4 * 5

x = 130/28

x = 65/14

x = 4 9/14

4 9/14 as a decimal is 4.64 which is close to 4.6666...

4 2/3 cups of water

starting with:    

5 + x - 12 = 2x - 7   

5 + x - 12 - x = 2x - 7 - x (subtract x from both sides)   

5 - 12 = x - 7 (combine and cancel x's from both sides)   

5 - 12 + 7 = x - 7 + 7 (add 7 to both sides)   

0 = x (add numbers together on both sides)       

so in order for the equation to be true, x must be 0.   

trying x = -0.5   

5 + x - 12 = 2x - 7 (original equation)   

5 + -0.5 - 12 = 2(-0.5) - 7 (plug in value of x)   

5 + -0.5 - 12 = -1 - 7 (did multiplication)   

-7.5 = -8 (did addition on both sides)       

since -7.5 is obviously not equal to -8, the value of -0.5 for x is wrong.   

trying x = 0   

5 + x - 12 = 2x - 7 (original equation)   

5 + 0 - 12 = 2(0) - 7 (plug in value of x)   

5 + 0 - 12 = 0 - 7 (did multiplication)   

-7 = -7 (did addition on both sides)       

since -7 equals -7, that demonstrates that the value of 0 for x is correct.   

trying x = 1   

5 + x - 12 = 2x - 7 (original equation)   

5 + 1 - 12 = 2(1) - 7 (plug in value of x)   

5 + 1 - 12 = 2 - 7 (did multiplication)   

-6 = -5 (did addition on both sides)       

since -6 is obviously not equal to -5, the value of 1 for x is wrong.

the answer is 13

step-by-step explanation:

5*5=25

12*12=144

25+144=169

169^2=13