If x ≠ 0 and a ≠ 0, solve :
xa−a+bx=b(a+b)ax\dfrac{x}{a} - \dfrac{a + b}{x} = \dfrac{b(a + b)}{ax}ax−xa+b=axb(a+b)
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Given,
⇒xa−a+bx=b(a+b)ax⇒x2−a(a+b)ax=ab+b2ax⇒x2−a2−abax×ax=ab+b2⇒x2−a2−ab=ab+b2⇒x2=a2+ab+ab+b2⇒x2=a2+2ab+b2⇒x2=(a+b)2⇒x2−(a+b)2=0⇒(x−(a+b))(x+(a+b))=0⇒x=a+b or x=−(a+b).\Rightarrow \dfrac{x}{a} - \dfrac{a + b}{x} = \dfrac{b(a + b)}{ax} \\[1em] \Rightarrow \dfrac{x^2 - a(a + b)}{ax} = \dfrac{ab + b^2}{ax} \\[1em] \Rightarrow \dfrac{x^2 - a^2 - ab}{ax} \times ax = ab + b^2 \\[1em] \Rightarrow x^2 - a^2 - ab = ab + b^2 \\[1em] \Rightarrow x^2 = a^2 + ab + ab + b^2 \\[1em] \Rightarrow x^2 = a^2 + 2ab + b^2 \\[1em] \Rightarrow x^2 = (a + b)^2 \\[1em] \Rightarrow x^2 - (a + b)^2 = 0 \\[1em] \Rightarrow (x - (a + b))(x + (a + b)) = 0 \\[1em] \Rightarrow x = a + b \text{ or } x = -(a + b).⇒ax−xa+b=axb(a+b)⇒axx2−a(a+b)=axab+b2⇒axx2−a2−ab×ax=ab+b2⇒x2−a2−ab=ab+b2⇒x2=a2+ab+ab+b2⇒x2=a2+2ab+b2⇒x2=(a+b)2⇒x2−(a+b)2=0⇒(x−(a+b))(x+(a+b))=0⇒x=a+b or x=−(a+b).
Hence, x = a + b or -(a + b).
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Find the value of x, if a + 7 = 0; b + 10 = 0 and 12x2 = ax - b.
Use the substitution 2x + 3 = y to solve for x, if 4(2x + 3)2 - (2x + 3) - 14 = 0.
Solve :
(1200x+2)(x−10)−1200=60.\Big(\dfrac{1200}{x} + 2\Big)(x - 10) - 1200 = 60.(x1200+2)(x−10)−1200=60.
If x2 - 3x + 2 = 0, values of x correct to one decimal place are :
2.0 and 1.0
2.0 or 1.0
3.0 and 2.0
3.0 or 2.0