Step-by-step explanation:
x²-y²=12
(x-y)(x+y)=12
but x-y=4
4(x+y)=12
x+y=12/4
x+y=3
lets make x the subject of the formula
x=3-y
since x-y=4
(3-y)-y=4
3-y-y=4
-2y=1
y=-1/2
then x=3-y
x=3-(-1/2)
x=(6--1)/2
x=7/2
therefore; x²+2xy+y
=(7/2)²+2×7/2×-1/2+(-1/2)
=49/4-7/2-1/2
=(49-14-2)/4
=33/4
=8.25
=8
Exactly like the previous question you posted.
-3x² - 9x = 0
Divide each side of the equation by -3 :
x² + 3x = 0
Factor the left side:
x (x + 3) = 0
This is true if x=0 or if x=-3 .
Answer:
1/4 chance (this is equal to 25% as a percentage or 0.25 as a decimal)
Step-by-step explanation:
There are 4 balls and only one can be first. As there is only 1 yellow ball, there is 1/4 chance that the yellow ball is picked first.
The temperature got colder by 11 regress
1/3 is 0.33.. and 1/4 is .25 , so the answer is 1/4