Answer:
x = -2 ±sqrt( 19)
Step-by-step explanation:
x^2 + 4x = 15
Take the coefficient of x
4
Divide by 2
4/2 =2
Square it
2^2 = 4
Add it to each side
x^2 + 4x+4 = 15+4
(x+2)^2 = 19
Take the square root of each side
sqrt( (x+2)^2) =±sqrt( 19)
x+2 = ±sqrt( 19)
Subtract 2 from each side
x+2-2 = -2 ±sqrt( 19)
x = -2 ±sqrt( 19)
Answer: 1st, 3rd, and 4th functions
Step-by-step explanation:
Assuming k(x)=9x^2, all the other functions have inverses because they are linear, meaning they must be one-to-one.
Answer:
£6.72
Step-by-step explanation:
10% of 5.60=0.56
0.56×2=1.12
5.60+1.12=£6.72
Ok so assuming that the 'x' means multiply and not 'x' as in placeolder we do
PEMDAS
parenthaseees
exponents
multipilcation or division
additon or subtraction
parethasees simplify first
(8+7)=15
(9-3)=6
now we have
2x(15)-6/2x(6)
multiply
2x15=30
6/2x6=36/2=18
now we have
30-18
12
answer is 12