Use the quadratic formula to find:
x
=
1
±
√
85
5
Explanation:
5
x
2
−
10
x
−
12
is of the form
a
x
2
+
b
x
+
c
with
a
=
5
,
b
=
−
10
and
c
=
−
12
This has discriminant
Δ
given by the formula:
Δ
=
b
2
−
4
a
c
=
(
−
10
)
2
−
(
4
×
5
×
−
12
)
=
100
+
240
=
340
=
2
2
⋅
85
This is positive, but not a perfect square, so the quadratic equation has a pair of irrational roots, given by the quadratic formula:
x
=
−
b
±
√
b
2
−
4
a
c
2
a
=
−
b
±
√
Δ
2
a
=
10
±
√
340
10
=
10
±
2
√
85
10
=
1
±
√
85
5
The second choice than the fir2nd choice than the first choice for the second question
Answer: B
Step-by-step explanation:
In the systems of equation it already gives you the solution for x which is -2 so all you have to do is substitute -2 into the first equation and solve for y.
y= 2/3x + 3
x= -2
Substitute x for -2
y = 
y= 
+ 
y = 
so now you have the solution like this 
Its representedf by 2 polygons(triangles)
first one :
24-20=4
11-6=5
second:
24-14=10
11-7=4
B. frind area of 2 small trianges
a=(base x height )/2
first=4x5/2=10ft square
second=10x 4/2=20ft square
add them=10+20=30
rectangle24x 11=264
264-30=234
