Question

Find the value of a so that f(x) = 7.

x=

Answer 1

`\quad \huge \quad \quad \boxed{ \tt \:Answer }`

`\qquad \tt \rightarrow \:x = -3`

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`\large \tt Solution \: :`

f(x) represents the value of y in a function for its corresponding value of x.

We need to find the value of x, when f(x) = y = 7

That is :
`{ \tt -3 }`

[ can be concluded by graph only ]

Method - 2 :

we can take any two points lying on the curve and find its equation, then put the value of y, and we will get our required value of x ~

So, by two point form : points (2 , 2) and (-2 , 6)

`\qquad \tt \rightarrow \: y - 2 = \bigg( (6 - 2)/( - 2 - 2) \bigg)(x - 2)`

`\qquad \tt \rightarrow \: y - 2 = \bigg( (4)/( - 4) \bigg)(x - 2)`

`\qquad \tt \rightarrow \: y - 2 = - 1(x - 2)`

`\qquad \tt \rightarrow \: y - 2 = - x + 2`

`\qquad \tt \rightarrow \: x + y = 4`

Now, put y = 7, you will get value of x ~

`\qquad \tt \rightarrow \: x + 7 = 4`

`\qquad \tt \rightarrow \: x = 4 - 7`

`\qquad \tt \rightarrow \: x = - 3`

Answered by : ❝ AǫᴜᴀWɪᴢ ❞