C the answer to your question is C
$90.10 is the total because if you multiple 85 x .06 is gives you 5.10 then you add 5.10 to 85.
Answer:
(6, 0)
Step-by-step explanation:
x+3y=6
x=6-3y
subsitute x into the first equation
(6-3y)+3y=6
6-6y=6
-6y=0
y=0
Do the next equation
x=6-3(0)
x=6
Answer:
x = -6
Step-by-step explanation:
5x² + 60x + 180 = 0
5 x 180 = 900
you need 2 numbers that multiplies into 900 and adds into 60. these numbers are 30 and 30. now we can rewrite it
5x² + 30x + 30x + 180 = 0.
split it in half and factorise
5x(x + 6) + 30(x + 6) = 0
this means the brackets are:
(5x + 30)(x + 6) = 0
5x + 30 = 0
5x = -30
x = -6
x + 6 = 0
x = -6
therefore, x = -6.