X = 0
<span>6y - 5x = 0 so it intersects x=0 at (0,0)
</span>
<span>x + 3y = 21
</span>so it intersect x=0 at (0,7)
multiply by 2
<span>2x + 6y = 42
subtracting 6y - 5x = 0
7x = 42
x = 6
so the third line intersects w second line at (6,5)
6. area of triangle = 1/2*base*height
= 1/2*7*6
=21
7. volume = volume of 2 cones
cone volume = 1/3*pi*radius^2*height
lower cone: radius=6, height=5
upper cone: radius=6, height=7-5=2
volume = 1/3*pi*6^2*(5+2)
=84pi
=263.89
</span>
( 30 / 100 ) * (15.40 ) = ( 3 / 10 )* (15.40) = 36.20 / 10 = 3.62$.
Answer: D
Step-by-step explanation:

Let's take one of the equations and solve for a variable to use the substitution method.

Now replace this in the first equation.

Separate the terms.

Solve 20/5

Subtract 4 from both sides to isolate y.


Solve the difference.



Multiply by the reciprocal or the inverted fraction that is next to y to isolate it.


Now, in order to find x, replace y in any of the two equations.

(1): "c0" was replaced by "c^0".
(2): Dot was discarded near "1.j". 1 more similar replacement(s)
Unauthorized use of the imaginary unit "i" or syntax error in complex arithmetic expression