Solve the equation x2+4x−21=0𝑥2+4𝑥−21=0 . Show your work to receive all the points. You can use the photo icon to upload a picture of your work or use the E symbol for math symbols.
To solve the equation 𝑥2+4𝑥−21=0, we will use the quadratic formula:
The quadratic formula is given by: 𝑥=−𝑏±√𝑏2−4𝑎𝑐/2𝑎
For the equation 𝑥2+4𝑥−21=0, we have 𝑎=1, 𝑏=4, 𝑐=−21
Substitute the values of 𝑎, 𝑏, and 𝑐 into the quadratic formula:
𝑥=−4±√42−4∗1∗−21/2∗1
𝑥=−4±√16+84/2
𝑥=−4±√100/2
𝑥=−4±10/2
𝑥=(−4+10)/2 or 𝑥=(−4−10)/2
𝑥=6/2 or 𝑥=−14/2
𝑥=3 or 𝑥=−7
Therefore, the solutions to the equation 𝑥2+4𝑥−21=0 are 𝑥=3 and 𝑥=−7.