X+y=28
xy=7
xy=7
divide both sides by x
y=7/x
sub 7/x for y in first equation
7/x+x=28
times both sides by x
7+x^2=28x
minus 28x from both sides
x^2-28x+7=0
use quadratic formula
if
ax^2+bx+c=0
x=
x=
x=
sub for y
y=7/x
y=
the reciprocals are
and
times first one by
and second by 7/7
evaluate the plus and minus yourself please, my head hurts
Answer:
x = 5 ; y = 14
Step-by-step explanation:
2x = 10
x = 5
y + 2 = 16
y = 14
The temperature started at 15 degrees.
It dropped 25 degrees.
Subtract 25 from 15:
15 - 25 = -10
The temperature was -10 degrees.
Answer: 133
Step-by-step explanation:
171 for 9 hours
171/9 equals 19
So 19 dollars per hour
7 hours times 19 dollars per hour equals 133
Maybe it’s b but i don’t really know, I’m just trying to help