If you would like to solve the system of equations, you can do this using the following steps:
4x^2 + 9y^2 = 72
2x - y = 4 ... 2x - 4 = y
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<span>4x^2 + 9y^2 = 72
</span><span>4x^2 + 9 * (2x - 4)^2 = 72
</span>4x^2 + 9 * (4x^2 - 16x + 16) = 72
4x^2 + 36x^2 - 144x + 144 = 72
40x^2 - 144x + 144 - 72 = 0
40x^2 - 144x + 72 = 0
10x^2 - 36x + 18 = 0
5x^2 - 18x + 9 = 0
(5x - 3) * (x - 3) = 0
1. 5x - 3 = 0 ... 5x = 3 ... x = 3/5
2. x = 3
<span>1. y = 2x - 4 = 2 * 3/5 - 4 = 6/5 - 20/5 = -14/5
2. y = 2x - 4 = 2 * 3 - 4 = 6 - 4 = 2
1. (x, y) = (3/5, -14/5)
2. (x, y) = (3, 2)
The correct result would be </span>(3/5, -14/5) and <span>(3, 2).</span>
Answer:
To add percentages, you have to make the percentage into a decimal with "1" as the whole number if it's lower than 100%.
So, $60 x 1.60 =
$96.00
The original price of the pair of shoes were: $96.00
In 5 years it grew 6 mill (181-175=6). Formula: 6(20/5)+181=X. multiply 6 by 4 (the number of five years in twenty years): 24. 24+181=205 million :)
