Step-by-step explanation:
15a)
Subtract both sides by 21
15b)
7 and -3 multiply to -21 and add to 4
The factors are (x+7)(x-3)
15c)
x+7 =0
x=-7
x-3=0
x=3
Answer: 3 , 76
Step-by-step explanation:
Khan Academy
I just took it i hope it helps give some feedback tnx.
Answer:
180 pages
Step-by-step explanation:
let x be the number of pages in the book , then
x + 40 = x ( multiply through by 9 to clear the fraction )
7x + 360 = 9x ( subtract 7x from both sides )
360 = 2x ( divide both sides by 2 )
180 = x
The total number of pages in the book is 180
Desmos graphing calculator will draw this graph for you.
draw 2 curves
y = x^4 + x^3
and
y = 4x^2 + 4x
The roots are the points where the 2 curves intersect.
You can see by simple substitution that one root is zero.
x^4 + x^3 - 4x^2 - 4x = 0
f(2) = 16 + 8 - 4(4) - 4(2) = 0 so 2 is another root
f(-2) = 16 - 8 - 16 + 8 = 0 so -2 is another root
f(-1) = 1 - 1 - 4 + 4 = 0 so -1 is the other root
The answer is A
