4
)
10(x+6)+8(x−3)=5(5x−4)
2 Expand.
10
x
+
60
+
8
x
−
24
=
25
x
−
20
10x+60+8x−24=25x−20
3 Simplify
10
x
+
60
+
8
x
−
24
10x+60+8x−24 to
18
x
+
36
18x+36.
18
x
+
36
=
25
x
−
20
18x+36=25x−20
4 Subtract
18
x
18x from both sides.
36
=
25
x
−
20
−
18
x
36=25x−20−18x
5 Simplify
25
x
−
20
−
18
x
25x−20−18x to
7
x
−
20
7x−20.
36
=
7
x
−
20
36=7x−20
6 Add
20
20 to both sides.
36
+
20
=
7
x
36+20=7x
7 Simplify
36
+
20
36+20 to
56
56.
56
=
7
x
56=7x
8 Divide both sides by
7
7.
56
7
=
x
7
56
=x
9 Simplify
56
7
7
56
to
8
8.
8
=
x
8=x
10 Switch sides.
x
=
8
x=8
Your answer is
X=8
For this case we have the following system of equations:
5x + 3y = 17
-8x - 3y = 9
We can rewrite the system like:
Ax = b
Where,
A = [5 3; -8 -3]
b = [17; 9]
x = [x; y]
The determinant of matrix A is given by:
lAl = ((5) * (- 3)) - ((3) * (- 8))
lAl = (-15) - (-24)
lAl = -15 + 24
lAl = 9
Answer:
The determinant for solving this linear system is:
lAl = 9
The area of the trapizoif is 97.5
L=R*angle, but the angle *must* be in radians. So, just translate 43 degrees into radians: 43 * pi / 180, and you'll get:
L = 42 * ( 43 * pi / 180 ) ~ 31.504666, which rounded to the nearest hundredth is 31.50 cm.
2 1/4 is already simplified but to make it into a mixed number the answer is 9/4
