Advertisements
Advertisements
Question
`8x^2-14x-15=0`
Solution
`8x^2-14x-15=0`
⇒`16x^2-28x-30=0`
⇒`16x^2-28x=30`
⇒`(4x)^2-2xx4x xx7/2+(7/2)^2=30+(7/2)^2`
⇒`(4x-7/2)^2=30+49/4=169/4=(13/2)^2`
⇒`4x-7/2=+-13/2`
⇒`4x=7/2=13/2 or 4x-7/2=13/2`
⇒`4x=13/2+7/2=20/2=10 or 4x=-13/2+7/2=6/2=-3`
⇒`x=5/2 or x=-3/4`
Hence, `5/2 and -3/4` are the roots of the given equation.
APPEARS IN
RELATED QUESTIONS
The difference of squares of two number is 88. If the larger number is 5 less than twice the smaller number, then find the two numbers.
Factorise : m2 + 5m + 6.
Find the value of k for which the following equations have real and equal roots:
\[x^2 - 2\left( k + 1 \right)x + k^2 = 0\]
The number of quadratic equations having real roots and which do not change by squaring their roots is
If one of the equation x2 + ax + 3 = 0 is 1, then its other root is
Solve equation using factorisation method:
`5/("x" -2) - 3/("x" + 6) = 4/"x"`
Solve the following equation by factorization
3(x – 2)2 = 147
Solve the following equation by factorization
x2– 4x – 12 = 0,when x∈N
Solve the following equation by factorization
`sqrt(3x + 4) = x`
Solve the following equation by factorisation :
3x2 + 11x + 10 = 0
