Answer:
Below
Step-by-step explanation:
● x^2 + 11x + 121/4 = 125/4
Substract 125/4 from both sides:
● x^2 + 11x + 121/4-125/4= 125/4 -125/4
● x^2 + 11x - (-4/4) = 0
● x^2 +11x -(-1) = 0
● x^2 + 11 x + 1 = 0
This is a quadratic equation so we will use the determinanant (b^2-4ac)
● a = 1
● b = 11
● c = 1
● b^2-4ac = 11^2-4*1*1 = 117
So this equation has two solutions:
● x = (-b -/+ √(b^2-4ac) ) / 2a
● x = (-11 -/+ √(117) ) / 2
● x = (-11 -/+ 3√(13))/ 2
● x = -0.91 or x = -10.9
Round to the nearest unit
● x = -1 or x = -11
The solutions are { -1,-11}
X+y+z=51
y=2z
z=9+x
subsitute those
x+2z+9+x=51
x+2(9+x)+9+x=51
x+18+2x+9+x=51
4x+27=51
minus 27 both sides
4x=24
divide by 4
x=6
sub back
z=9+x
z=9+6
z=15
y=2z
y=2(15)
y=30
the numbers are
6,30,15
Answer:
a = 4 and b = - 30
Step-by-step explanation:
Expand the left side and compare like terms on both sides, that is
(x + 2)(x - 3)(x + 5) ← expand the first pair of factors using FOIL
= (x² - x - 6)(x + 5) ← distribute
= x³ + 5x² - x² - 5x - 6x - 30 ← collect like terms
= x³ + 4x² - 11x - 30
Compare like terms with x³ +ax² - 11x + b
4x² and ax² ⇒ a = 4
+ b and - 30 ⇒ b = - 30
15ft per sec would be the unit rate.
42 and 14
explanation:
x+y = 56
x = 3y
Substitute for x in the first equation:
x + y = 56
x = 3y
3y + y = 56
Combine like terms:
4y = 56
Divide both sides by 4:
y = 14
So if y = 14, and x = 3y, then x = 42.
Now substitute for both x and y in both of the original equations to prove they are the correct values.
x + y = 56
x = 42
y = 4
42 + 14 = 56
56 = 56
x = 3y
x = 42
y = 14
42 = 3*14
42 = 42
So the two numbers, x and y, are 42 and 14.
