SOLUTION: 1) x squared - 4x + 5 = 0 2) C squared + 6c + 8 = 0 3) a squared - 2a = -1 4) n squared - 7n = -10

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Question 277147: 1) x squared - 4x + 5 = 0
2) C squared + 6c + 8 = 0
3) a squared - 2a = -1
4) n squared - 7n = -10
Answer by CharlesG2(834) About Me  (Show Source):
You can put this solution on YOUR website!
1) x squared - 4x + 5 = 0
x^2 - 4x + 5 = 0
use ax^2 + bx + c = 0
a = 1, b = -4, c = 5
x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+
x+=+%284+%2B-+sqrt%28+16+-+4%2A5+%29%29%2F2+
x+=+%284+%2B-+sqrt%28+16+-+20+%29%29%2F2+
x+=+%284+%2B-+sqrt%28+-4+%29%29%2F2+
x+=+%284+%2B-+2i%29%2F2+
x+=+2+%2B-+i+
check: (2+i)^2 - 4(2+i) + 5 = 0
4 + 4i - 1 - 8 - 4i + 5 = 0
4 - 1 - 8 + 5 + 4i - 4i = 0
3 - 8 + 5 = 0
- 5 + 5 = 0
0 = 0
(2-i)^2 - 4(2-i) + 5 = 0
4 - 4i - 1 - 8 + 4i + 5 = 0
4 - 1 - 8 + 5 = 0
3 - 8 + 5 = 0
- 5 + 5 = 0
0 = 0
2) C squared + 6c + 8 = 0
c^2 + 6c + 8 = 0
(c+2)(c+4) = 0 (using foil this does come out to the above)
c = -2 or c = -4
3) a squared - 2a = -1
a^2 - 2a = -1
a^2 -2a + 1 = 0
(a-1)(a-1) = 0
one answer a=1
4) n squared - 7n = -10
n^2 - 7n = -10
n^2 - 7n + 10 = 0
(n - 2)(n - 5) = 0
n = 2 or n = 5