Question

The square of a number is 3 less than four times the number. Which values could be the number?

(More than one answer)
a. 3
b. 0
c. 1
d. -3
e. -1

Answer 1

A and C.

Explanation:

We are given that: "The square of a number (which we can call x) is three less than four times the number."

In other words:

`\displaystyle x^2 = 4x - 3`

Hence solve for x by isolating the equation and factoring:

`\displaystyle \begin{aligned} x^2 - 4x + 3 & = 0 \\ \\ (x-1)(x-3) & = 0 \\ \\ x & = 1 \text{ or } x = 3 \end{aligned}`

In conclusion, our answers are A and C.