Rearrange to make the right hand side of the equation zero.
Then factorise and solve.
Example:
a^2 + 2a = 3
a^2 +2a -3 = 0
(a-1)(a+3) = 0
Either
a = 1 or a = 03
Question:
2x2 - 7 = 1
Solve the above question!
Quadratic Equations for you to solve please read?
2009-06-04 8:26 am
回答 (5)
2009-06-04 10:07 am
✔ 最佳答案
a^2 - b^2 ≡ (a + b)(a - b)2x^2 - 7 = 1
2x^2 - 7 - 1 = 0
2x^2 - 8 = 0
2(x^2 - 4) = 0
(x^2 - 2^2) = 0/2
(x + 2)(x - 2) = 0
x + 2 = 0
x = -2
x - 2 = 0
x = 2
∴ x = ±2
2009-06-04 3:36 pm
2 x^2 = 8
x^2 = 4
x = ± 2
x^2 = 4
x = ± 2
2009-06-04 3:34 pm
2x^2 - 7 = 1
2x^2 = 8
x^2 = 4
so x = 2 or -2
2x^2 = 8
x^2 = 4
so x = 2 or -2
2009-06-04 3:57 pm
what lunacy is this, I ask . .trying to force a value of one constant upon another! This is an outrage . .!
2009-06-04 3:43 pm
2x^2-7 = 1
2x^2-7-1 = 0
2x^2-8 = 0
x^2-4 = 0
(x-2)(x+2) = 0
either x=2 or x= -2
2x^2-7-1 = 0
2x^2-8 = 0
x^2-4 = 0
(x-2)(x+2) = 0
either x=2 or x= -2
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