Solve the system of equations
Y = 2x
X - Y = 10

x=-10, y=-20

Step-by-step explanation:

first you substiture the y in the second equation with the first

x-2x=10

then solve

1x-2x=-1

-x=10

multiply both sides by a negative to make the varible a

positive

x=-10

now we substitue the x in the first equation with -10

y=2(-10)

y=-20

the circle one

t = 3

step-by-step explanation:

put t = 3 in this expression :

(3²-1)(3²-2)(3² - 3)(3² - 4) = 8×7×6×5 = 56×30 = 1680