Answer:
b. 36 years
Step-by-step explanation:
Today
Nirmala = x years
Rahul = 3x years
In 13 years
Nirmala = 3x + 13 years
Rahul = 2(x+13) - 1
3x + 13 = 2(x+13) - 1
3x + 13 = 2x + 26 - 1
3x + 13 = 2x + 25
3x - 2x = 25 - 13
x = 12
Nirmala = x years
= 12 years
Rahul = 3x years
= 3(12)
= 36 years
The age of Rahul today is 36 years
You can make it easier by replacing x^n with another variable, factoring, then putting x^n back in the end.
Using exponent and algebra rules, rewrite x^2n - 2x^n + 1 as
(x^n)^2 - (2 x x^2) + 1
Then, let x^n = m.
m^2 - 2m + 1
Now factor that: (m - 1)^2
And now put x^n back: (x^n - 1)^2
Answer:
x=
3
5
+
1
5
√149 or x=
3
5
+
−1
5
√149
10+(-7)=3. Hope this helped :))
