Since p = x² - 7, you can substitute/plug in p for x² - 7
So:
(x² - 7)² - 4x² + 28 = 5
(p)² - 4x² + 28 = 5 You can factor out -4 from (-4x² + 28)
p² - 4(x² - 7) = 5 Plug in p
p² - 4p = 5 Subtract 5
p² - 4p - 5 = 0 Your answer is C
Answer:
Step-by-step explanation:
"Four times a number" in symbols is "4n."
F = 
express the equation with F on the left side
3F - 24 = s ( add 24 to both sides )
3F = s + 24 ( divide both sides by 3 )
F = 
3n+2n= 5n
22+38=60
180-60=60
60=5n
n=12