2nd equation:
8 x-y=10 ⇒ y= 8 x-10
We will switch that in 1st equation:
8 x-10=x²+12 x+30, or:
x² + 4 x +40 = 0, a=1,B=4, c=40
Discriminant : D= b² - 4 ac= 16 - 160 = -144 and because it is negative there are no real solutions.
Answer: D)
Answer:
you have to finish posting the question in order to get a proper answer
I think you want to say the expression 3m2+2p2-15. The only thing you need to do is to replace the letter with the number. So the expression is 3*3^2+2*10^2-15=212.
She should get 84 in her fifth test to have an average of 80
(75 + 81 + 77 + 83 + x)/5 = 80
(316 + x)/5 = 80
[(316 + x)/5] (5) = 80(5)
316 - 316 + x = 400
316 + x = 400 - 316
x = 84
