Question

factorised form of r^2-10r+21 is
need answer with solution

Answer 1

Given,

A quadratic equation r²-10r+21 = 0

To Find,

The factorized form of this equation.

Solution,

By using the middle term splitting method we will factorize the given quadratic equation,

r²-10r+21 = 0

Now, splitting the middle term of this equation

r²-7r-3r+21 = 0

r(r-7)-3(r-7) = 0

(r-7)(r-3) = 0

So, the value of r for which this quadratic equation satisfies is r = 7 or r = 3.

Hence, the factorized form of r²-10r+21 is (r-7)(r-3).

Answer 2

Answer:

Factorized the given data.

Explanation:

Given:

$r^{2}-10r+21 =0$

Calculations:

$r^{2}-10r+21 =0\\r^{2}-7r-3r+21 =0\\r^{2}-7r-3(r-7)=0\\r(r-7)-3(r-7)=0\\r=3\\r=7$

Therefore, factorized,

$(r-7)(r-3)$

Hence option b) is correct.