Question

Explain how to solve x² + 6x-8 using algebraic methods and graphs. Round to the nearest hundredth when necessary.

Answer 1

For graphical method get the table of values. These gives the coordinates to be used to make the graph OR Plotting graph digitally, by using graphing calculator, typing the equation results to the graph.

The value of x is x = 1.12 OR -7.12 to the nearest hundredth

For algebraic method, solve the equation as follows

To solve the quadratic equation x² + 6x - 8 wit quadratic Formula:

x =
`(-b \pm √(b^2 - 4ac))/(2a)`

Where a = 1, b = 6, and c = -8

x =
`(-6 \pm √(6^2 - 4(1)(-8)))/(2(1))`

x =
`(-6 \pm √(36 + 32))/(2)`

x =
`(-6 \pm √(68))/(2)`

where √68 = 2√17

x = (-6 ± 2√17) / 2

x = -3 + √17 = 1.12 to the nearest hundredth

x = -3 - √17 = -7.12 to the nearest hundredth