What is the solution of x+2y=4 and 3x-2y=-12

solution

is

you minus smallest x(you minus because the opposite of positive ia negative)

so you do x-x=0 and 4-x=3

so 2y/2. and 3÷2

so x is 1.5

for the 2nd question 3x -2y= -12

you do add 2y on both sides

so -2y+2y =0 and -12 +2y= -10 y

so 3x/3 and -10y /3

x= - 3.3333333333

??

(b) 240

step-by-step explanation:

first, we use the pythagorean formula using the given side lengths to find x. then we use x to find the side lengths. then we add the side lengths to find the perimeter.

pythagorean theorem formula:

a^2 + b^2 = c^2

(x - 20)^2 + (x - 40)^2 = x^2

x^2 - 40x + 400 + x^2 - 80x + 1600 = x^2

x^2 -120x + 2000 = 0

(x - 100)(x - 20) = 0

x - 100 = 0 or x - 20 = 0

x = 100 or x = 20

we see that the solution x = 20 must be discarded because it will give a negative side length and a side length of 0. the only valid solution is x = 100.

perimeter = sum of the lengths of the sides

perimeter = x + x - 20 + x - 40

perimeter = 3x - 60

replace x with 100.

perimeter = 3(100) - 60

perimeter = 300 - 60

perimeter = 240