Answer:
168
Step-by-step explanation:
3 + .11x = 21.48
.11x = 18.48
x = 168
Answer:
It is a perfect square. Explanation below.
Explanation:
Perfect squares are of the form
(
a
+
b
)
2
=
a
2
+
2
a
b
+
b
2
. In polynomials of x, the a-term is always x.(
(
x
+
c
)
2
=
x
2
+
2
c
x
+
c
2
)
x
2
+
8
x
+
16
is the given trinomial. Notice that the first term and the constant are both perfect squares:
x
2
is the square of x and 16 is the square of 4.
So we find that the first and last terms correspond to our expansion. Now we must check if the middle term,
8
x
is of the form
2
c
x
.
The middle term is twice the constant times x, so it is
2
×
4
×
x
=
8
x
.
Okay, we found out that the trinomial is of the form
(
x
+
c
)
2
, where
x
=
x
and
c
=
4
.
Let us rewrite it as
x
2
+
8
x
+
16
=
(
x
+
4
)
2
. Now we can say it is a perfect square, as it is the square of
(
x
+
4
)
.
An acute triangle
Step-by-step explanation:
Using a calculator, these measurements fit an acute scalene triangle.
Use linear combination to solve this. It is much faster than substitution. I would start by multiplying the bottom equation by -1.
<span>4x-7y=3
-x+7y=15</span>
Then, add the two equations together. The result is:
3x=18.
You've eliminated one variable. Now you can solve for the other one.
Divide both sides by 3 to get
x=6
Plug this into one of the original equations, then solve for y
-(6)+7y=15
7y=21
y=3
Check your work by plugging these values into both equations to see if they remain true