Need help! Select the approximate values of x that are solutions to f(x) =0, where f(x) = -4x^2 +5x+7

Question

a) {2.09, -0.84}

b) {-4,5}

c) {-1.25,-1.75}

d) {-0.57,0.71}

Answer 1

This is a computer generated solution

Equation to solve is:

−4x2+5x+7=0
The solutions are:

x1=58+18137−−−√x2=58−18137−−−√
Explanation

First we will simplify equation by multiplying both sides with -1 . After multiplying we have the following equation.

4x2−5x−7=0
STEP1: Find coefficients a , b and c.

In this example a=4,b=−5,c=−7

STEP2: Plug in the values for a, b, and c into the quadratic formula

x1,2=−b±b2−4ac−−−−−−−√2a
x1,2=−(−5)±(−5)2−4⋅4⋅(−7)−−−−−−−−−−−−−−−√2⋅4
STEP3: Simplify expression under the square root.

x1,2=5±137−−−√8
STEP4: Solve for x

x1=5 + 137−−−√8=58+18137−−−√
x2=5 − 137−−−√8=58−18137−−−√