Solve the system by the substitution method.
xy=9
x^2+y^2=82

Xy=9 and
x^2+y^2=82
we manipulate the first equation to get
xy=9
divide both sides by x
y=9/x
subtitute y=9/x into x^2+y^2=82
x^2+(9/x)^2=82
x^2+81/x^2=82
multiply both sides by x^2 to get rid of the denomator (bottom number)
x^4+81=82
subtract 81 from both sides
x^4=1
find the fourth root of 1 and get
x=1
subtitute into origoal equation  xy=9 and get
(1)y=9
y=9

yes

step-by-step explanation:

always plug in x. in this case, x equals 4.

i'm going to first solve 4(2+3x)

1) 4(2+3(4)) use pemdas to solve.

i'm going to multiply whats in the parenthesis first, so 3 times 4=12.

2)4 (2+12) i'm then going to multiply 4 by both numbers in the parenthesis (because multiplying comes before adding)

4 times 2= 8.   4 times 12= 48

4) (8+48)= 56 (answer)

i'm then going to solve 8+12x and plug in 4 for x.

1) 8 +12(4)

multiplying comes before adding, so i'm gonna multiply 12 and 4.

12 times 4= 48.

2) 8+48=56

both equal the same!

The correct answer is $90