the difference of squares of two numbers is 180 the square of smaller number is 8 times the larger number find two number
Answers
Answer:
18,12
Step-by-step explanation:
let a,b be the two no.s
given, a²-b² = 180 ------------- I
& b² = 8a -------------------- II
substitute II in I, we get,
a² - 8a = 180
a² - 8a- 180=0
on factorising,
(a+10)(a−18) = 0
=> either a+10 =0 => a= -10 (Eliminate the negative no. as square of no. cannot be negative. see II )
or a-18 = 0 => a = 18
by II , b²=8*18
=> b² = 12²
=> b=12
Answer:
We have,
Let the large number is =x
Square of smaller number is =8x
Now, According to given question,
x2−8x=180
⇒x2−8x−180=0
⇒x2−(18−10)x−180=0
⇒x2−18x+10x−180=0
⇒x(x−18)+10(x−18)=0
⇒(x−18)(x+10)=0
⇒x−18=0,x+10=0
⇒x=18,x=−10
⇒x=−10,18
Either
x=−10 and x=18
x=18 is true (Positive value)
Now, square of small number
=18x=18×8=144
144
=12