So x times y=15
x+y=12
solve
x+y=12
subtract x from both sides
y=12-x
subsitute
xy=15
x(12-x)=15
distribute
12x-x^2=15
subtract (12x-x^2) from both sides
0=x^2-12x+15
use quadratic formula which is
x=

where you have
0=ax^2+bx+c
so
a=1
b=-12
c=15
subsitute
x=

x=

x=

x=

x=6+/-

x=6+

or 6-

or aprox
x=10.5826 or 1.41742
the numbers are 10.5826 and 1.41742
Interior angles of a triangle, when added, = 180
so < A + < B + < C = 180
41 + 90 + < C = 180
131 + < C = 180
< C = 180 - 131
< C = 49
< C + < D + < E = 180.....because when added they form a line
49 + 32 + < E = 180
81 + < E = 180
< E = 180 - 81
< E = 99 <======
<span>To find this answer, the second value needs to be converted into an improper fraction. (-1 1/6) becomes (-7/6) when properly converted. Then, 5/6 + (-7/6) becomes the same as (5/6) - (7/6). Since both have common denominators, the numerators can simply be subtracted: (5-7) = -2. This leaves a sum of (-2/6), which can be reduced to (-1/3).</span>
Since you are writing this in slope-intercept equation you will want to isolate the y. Therefore move the -8x over making it into -2y=8x+10. Then simply divide by the -2. And your equation will be y=-4x-5.