Question

Find value of 'n' if 'u' = 45

u=2n² -5n + 3​

Answer 1

Hey! there . Thanks for your question :)

Answer:

• n = 6 and -7/2

Step-by-step Explanation:

In this question we are given with an equation that is u = 2n² - 5n + 3 . Also we are given with the value of u that is 45 .

And we are asked to find the value of 'n'

For solving this equation we have to use middle term splitting method .

Given Equation :

• u = 2n² - 5n + 3 or,

• 2n²- 5n + 3 = u

First of all we are substituting value of u ( 45 ) in the given equation :

• 2n² - 5n + 3 = 45

• 2n² - 5n + 3 - 45 = 0

• 2n² - 5n - 42 = 0

Now , splitting the middle term :

• 2n² + 7n -12n - 42 = 0

• n ( 2n + 7 ) - 6 ( 2n + 7 ) = 0

• ( n - 6 ) ( 2n + 7 ) = 0

Now value of n :

1)

• n - 6 = 0

• n = 6

2)

• 2n + 7 = 0

• 2n = -7

• n = (-7)/2

Therefore , value of n are 6 and (-7)/2 .

• Hope it'll help you!! :)