Answer:
x=1 y = -1/2
(1,-1/2)
Step-by-step explanation:
7x-2y=8
5x+2y=4
I would use elimination since we have 2y in one equation and -2y in the other
7x-2y=8
5x+2y=4
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12x = 12
Divide each side by 12
12x/12 = 12/12
x =1
The substitute back into equation 2
5(1) +2y = 4
5 +2y = 4
Subtract 5
5-5+2y = 4-5
2y = -1
Divide by 2
2y/2 = -1/2
y = -1/2
There are conversion tables everywhere that assist you in changing a different unit into another. Depending on what it is, you can also compare weight into water, cm into m and backwards.
(x-2)squared +y squared=20
5*23
Note 23 = 20 + 3
5*23 = 5*(20 + 3) and by distributive property
5*23 = 5*20 + 5*3 = 100 + 15 = 115
= 115