5x+2y+ 2z=7 15x+6y +6z=7 2x-5y+2z=4

for equation 1 is 5, 2 and 0

Step-by-step explanation:

Step 1: you know the answer to this eqution is 7 but you don't know what numbers do you  put in place of the variables to get 7 so you have to figure out the numbers.

Step 2: 5x + 2y + 2z = 7 okay so the number is very low and if we multiply 5, 2, or 2 by 2 then we won't get 7 so the answer will most likely be multiply each number by 1 EXCEPT the last 2.

Step 3: so lets change the equation 5 x 1 + 2 x 1 + 2 x 0= 7 and lets solve it 5 + 2 + 0 = 7

So your answer is 5, 2 and 0  

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