Question

factorise 49a^2-81b^2
pls send fasr​

Answer 1

49a2-25b2

Final result :

(7a + 5b) • (7a - 5b)

Step by step solution :

Step 1 :

Equation at the end of step 1 :

(49 • (a2)) - 52b2

Step 2 :

Equation at the end of step 2 :

72a2 - 52b2

Step 3 :

Trying to factor as a Difference of Squares :

3.1 Factoring: 49a2-25b2

Theory : A difference of two perfect squares, A2 - B2 can be factored into (A+B) • (A-B)

Proof : (A+B) • (A-B) =

A2 - AB + BA - B2 =

A2 - AB + AB - B2 =

A2 - B2

Note : AB = BA is the commutative property of multiplication.

Note : - AB + AB equals zero and is therefore eliminated from the expression.

Check : 49 is the square of 7

Check : 25 is the square of 5

Check : a2 is the square of a1

Check : b2 is the square of b1

Factorization is : (7a + 5b) • (7a - 5b)

Final result :

(7a + 5b) • (7a - 5b)