This may not be very pretty.
(2x + 5) * (2x + 5) expanded is (use foil)
F = 4x^2
O = 2x * 5 = 10x
I = 2x + 5 = 10x
L = 25
Total = 4x^2 + 20x + 25
(x + 3)(x + 3) = x^2 + 6x + 9 by the same method
(2x + 7)(2x + 7) = 4x^2 + 28x + 49 Same method.
4x^2 + 20x + 25 + x^2 + 6x + 9 = 4x^2 + 28x + 49
5x^2 + 26x + 34 = 4x^2 + 28x + 49 Collect everything on the left.
x^2 - 2x - 15 = 0
(x - 5)(x + 3) = 0
x + 3 will have no meaning.
x - 5 = 0
x = 5
2x + 5 = 2*5 + 5 = 15
x + 3 = 5 + 3 = 8
2x+ 7 = 2*5 +7 = 17
Check
15^2 + 8^2 = 17^2
225 + 64 = ? 289
289 = 289
a = 15 <<<<< answer
b = 8 <<<<< answer
c = 17 <<<<< answer
Answer:
The sales price of the PS4 is $532.
Step-by-step explanation:
The system sells for $399 after giving 25% off on a Black Friday on the sales price.
Let the sales price of the PS4 system is $x.
Then after giving 25% discount the price will become
Therefore, 0.75x = 399
⇒ x = 532
Therefore, the sales price of the PS4 is $532. (Answer)
Answer:
y = (5/4)2^x
Step-by-step explanation:
The function value increases by a factor of 40/10 = 4 when x increases by 2. The function can be written as ...
y = (reference value)·(growth factor)^((x -reference)/(change in x for growth factor))
y = 10·4^((x-3)/2) . . . . . . using point (3, 10) as a reference
This can be simplified to ...
y = 10·2^(x -3) = 10/8·2^x
y = (5/4)2^x
Answer:
6 Miles and the cost is $4.50
Step-by-step explanation:
3+0.25=0.75x
3+0.50x
6=x
0.75x+?
0.75 x 6= 4.50
Answer:
(16, 11) or ( 16, 10 )
Step-by-step explanation: