What two numbers have a product of -2 and a sum of 7
1 answer:
<em>Greetings from Brasil...</em>
According to the statement of the question, we can assemble the following system of equation:
X · Y = - 2 i
X + Y = 7 ii
isolating X from i and replacing in ii:
X · Y = - 2
X = - 2/Y
X + Y = 7
(- 2/Y) + Y = 7 <em>multiplying everything by Y</em>
(- 2Y/Y) + Y·Y = 7·Y
- 2 + Y² = 7X <em> rearranging everything</em>
Y² - 7X - 2 = 0 <em>2nd degree equation</em>
Δ = b² - 4·a·c
Δ = (- 7)² - 4·1·(- 2)
Δ = 49 + 8
Δ = 57
X = (- b ± √Δ)/2a
X' = (- (- 7) ± √57)/2·1
X' = (7 + √57)/2
X' = (7 - √57)/2
So, the numbers are:
<h2>
(7 + √57)/2</h2>
and
<h2>
(7 - √57)/2</h2>
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Answer:
its five points...
Step-by-step explanation:
L=n-2, W=4+L=n+2
A=LW, since L=n-2 and W=n+2 we have:
A=(n-2)(n+2) so it could be this expression or the expansion
A=n^2-4
Answer:
57:38
Step-by-step explanation:
3/2(19):x
3:2
3x = 2 * 3/2 * 19
3x = 57
x = 19
Since the ratio is 3:2, then the scores at half-time were 57:38
