Step-by-step explanation:
f(-5)=-5(-5)²+4
f(-5)=5(25)+4
f(-5)=125+4
f(-5)=129
Answer:
16
Step-by-step explanation:
if 5 white cups and 8 green 10 white cups and 16 green
5 × 2 = 10
8 × 2 = 16
Answer:
(a) (7, -3)
(b) (-7, 3)
Step-by-step explanation:
4 1/3pt = how many cups
=17
Answer:
Length = 9units
Width = 7units
Step-by-step explanation:
It is said that the length is 2units more than the width
Assume that the width is x, then the length will be 2 + x
ie
Width = x
Length = 2 + x
Area of the rectangle = 63units
Area of rectangle = l * b
l - length of the rectangle
b - width of the rectangle
A = l * b
63 = (2 + x) * x
63 = ( 2 + x) x
63 = 2x + x^2
Let's rearrange it
x^2 + 2x - 63 = 0
Let's find the factor of 63
A factor that can be multiplied to give -63 and that can be added to give +2
Let's use -7 and +9
x^2 - 7x + 9x - 63 = 0
Separate with brackets
( x^2 - 7x) + ( 9x - 63) = 0
x( x - 7) + 9(x - 7) = 0
( x + 9)(x - 7) = 0
( x + 9) = 0
( x - 7) = 0
x + 9 = 0
x = -9
x - 7 = 0
x = 7
Note: the length of a rectangle can not be negative
So therefore,
x = 7
Length = 2 + x
= 2 + 7
= 9units
Width = x
= 7units
