X² - 4x - 77 = 0
( x + 7) ( x - 11)
x + 7 = 0
x - 11 = 0
x = -7
x = 11
This one is very simple.
create a simple equation to find out
15 = 12 + x
subtract 12 from each side
x= 3
the missing number is 3
or, to be even simpler, take the total, subtract the total from the number you know and the difference is the missing number.
hope I helped
ALSO, we can check going down vertically. 3 + 10 =13. this is the total listed at the bottom.
just fyi, if you spend x points on question, each user gets x/2 points (rounded up or down, I don't remember)
simple interest formula is
I=PRT
I=interest
P=principal
R=rate in decimal
T=time in years
assuming you mean that the principal is $2500 and not 2500 cents or 2500 of some other currency
interest=500
R=4%=0.04
I=PRT
500=(2500)(0.04)(T)
500=100T
divide both sides by 100
5=T
answer is 5 years
C is answer
N = 2s/a+1 you wrote h but you didn’t actually write an h in the formula so I assume you meant n