Answer:
25x^2 -1
Step-by-step explanation:
If you multiply parentheses:
(5x*5x) + (5x*-1) + (1*5x) + (1*-1)
25x^2 - 5x + 5x -1
25x^2 -1
A simpler way is to memorize this formula
(Square1 - square2)= (sqrt of square1- sqrt of square2)*(sqrt of square1 + sqrt of sqaure2)
Answer:
D. -4
Step-by-step explanation:
the slope formula is
m=(y2-y1)/(x2-x1)
(x2,y2) = (4,7)
(x1, y1) = (5,3)
So (7-3)/(4-5) = 4/-1 = -4
Answer:
8,000-24x
Step-by-step explanation:
there's 24 months in 2 years. If it's value decreased from 8,000 at a constant rate over a 2 year period, the equation would be 8,000-24x
answer: 60
age difference is 30 years
10x4=40
40-10=30
when she is 30 he will be 60 because 30(her age) + 30 (age difference) = 60
Answer:
x = 16
Step-by-step explanation:
The equation shown can be solved this way.
x^2 +(x -4)^2 = 20^2
x^2 +x^2 -8x +16 = 400
2x^2 -8x -384 = 0
x^2 -4x -192 = 0
(x -16)(x +12) = 0
The positive solution is ...
x = 16
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Since this makes use of the Pythagorean theorem, you've probably run across the 3-4-5 triangle. You often find scaled versions of it in algebra and geometry problems. Here, it is scaled by a factor of 4 to give a 12-16-20 triangle as half of the display screen.
The 3-4-5 triple is the only Pythagorean triple that is an arithmetic sequence. So, if the difference in side lengths is 4 and the diagonal is 5×4, you can be pretty certain that x = 4×4 and x-4 = 4×3.