28x + 44y = 964.40
21x + 33y = 723.30
Let's multiply the first equation by 4 and the second by -4
84x + 176y = 3857.6
-84x - 132y = -2893.2
Add the equations together.
0 + 44y = 964.4
Simplify
44y = 964.4
Divide both sides by 44
y = 964.4/44
Since we have the value of y, let's plug 964.4/44 into y for the first equation.
28x + 44(964.4/44) = 964.40
Simplify the left side
28x + 964.4 = 964.4
Subtract 964.4 from both sides
28x = 0
Divide both sides by 0
x = 0
In conclusion,
y = 964.4/44
x = 0
77.) x= {-5, 6}
78.) x= {-4, 9}
79.) x= {5/3, 2}
80.) x= {1/9, 3}
81.) x= {-6, 18}
82.) x= {-3√3 +4, 3√3 +4}
83.) x= {-7, -3}
84.) x= {-√85 +9 /2, √85 -9 /2}
A constant because it a number
