Question

Find the value of a if 55a = 30²−25​

Answer 1

Question:

55a=30²-25

Step-by-step explanation:

55a=900-25

55a=875

a=875/55

a=15.09

Answer 2

• As per the data given in the question, we have to find the value of the expression.

       Given data:- $55a=30^{2}-25^{2}.$

       To find:- the value of a.

       Solution:-

• When we observe the expression, here we will use the algebraic identities. A square minus b square is used to find the difference between the two squares without actually calculating the squares.

       $\Rightarrow a^{2}-b^{2}=(a+b)(a-b).$

      We will write as,

       $\Rightarrow 55a=30^{2}-25^{2}\\\Rightarrow 55a=(30+25)(30-25)\\\Rightarrow 55a=55\times5\\\Rightarrow a=\frac{55\times5}{55}\\\Rightarrow a=5.$

      Hence, the value will be $5.$