Step-by-step explanation:
well,
(y - 7)² = (y - 7)(y - 7)
remember how to multiply 2 expressions ?
you have to multiply every term of one expression with every term of the other expression and sum the results all up (incl. considering their individual signs, of course).
so, when we do the multiplication, we get
(y - 7)(y - 7) = y×y - 7×y - 7×y + (-7)×(-7) =
= y² - 14y + 49
and that is clearly different to y² - 49
FYI
y² - 49 is the result of
(y - 7)(y + 7)
because
y×y + 7×y - 7×y + (-7)(7) = y² - 49
Answer:
-23x^3+20x^4+25x^2+84x-84
Step-by-step explanation:
1 Expand by distributing sum groups.
4x^2(3x+5x^2-6)-7x(3x+5x^2-6)+14(3x+5x^2-6)
2 Expand by distributing terms.
12x^3+20x^4-24x^2-7x(3x+5x^2-6)+14(3x+5x^2-6)
3 Expand by distributing terms.
12x^3+20x^4-24x^2-(21x^2+35x^3-42x)+14(3x+5x^2-6)
4 Expand by distributing terms.
12x^3+20x^4-24x^2-(21x^2+35x^3-42x)+42x+70x^2-84
5 Remove parentheses.
12x^3+20x^4-24x^2-21x^2-35x^3+42x+42x+70x^2-84
6 Collect like terms.
(12x^3-35x^3)+20x^4+(-24x^2-21x^2+70x^2)+(42x+42x)-84
7 Simplify.
-23x^3+20x^4+25x^2+84x-84
Answer:
22 in
Step-by-step explanation:
<u>circumference of a circle = 2 π r</u>
where radius (r) = 7/2 in. = 3.5 in
C = 2 π (3.5)
= 22 in
Answer:
Step-by-step explanation:
4/x + 4/(x²-9) = 3/(x - 3)
4 / x + 4 / [( x - 3) ( x + 3 )] = 3 / ( x - 3 ) / * x ( x - 3 ) ( x + 3 )
Restrictions : x ≠ 0, x ≠ - 3 , x ≠ 3;
4 ( x + 3 ) ( x - 3 ) + 4 x = 3 x ( x + 3 )
4 ( x² - 9 ) + 4 x = 3 x² + 9 x
4 x² - 36 + 4 x - 3 x² - 9 x = 0
x² - 5 x - 36 = 0
x² - 9 x + 4 x - 36 = 0
x ( x - 9 ) + 4 ( x - 9 ) = 0
( x - 9 ) ( x + 4 ) = 0
x - 9 = 0, or : x + 4 = 0
Answer:
x = 9, x = - 4
Answer:
x = 3.16
Step-by-step explanation:
x * x = 10
square root both sides
x is appr. 3.16
