The right equations are a+c=30 (total number of people) and 8a+c=100 (total amount of money). So answers B and D cannot be right.
a+c=30 can be rewritten as c=30-a and filled into the second one:
8a + 30-a = 100 => 7a = 70 => a=10
That leaves answer A as the right one.
Answer:
X dot on graph (-0.333,0) Y dot on graph (0,1)
Step-by-step explanation:
It intercepts on the X line on (-0.33,0)
It intercepts on the Y line on (0,1)
Answer:
The area of the trapezoid is 
Step-by-step explanation:
we know that
The area of a isosceles trapezoid is equal to the area of two isosceles right triangles plus the area of a rectangle
step 1
<em>Find the area of the isosceles right triangle</em>
Remember that
In a isosceles right triangle the height is equal to the base of the triangle
we have

so

The area is equal to

substitute the values

step 2
Find the area of the rectangle
The area of the rectangle is equal to

we have
-----> is the height of the trapezoid
-----> the diagonal of the rectangle
Applying the Pythagoras Theorem

The area of the rectangle is

step 3
Find the area of the trapezoid

See attached for the solution
Answer:19.08
Step-by-step explanation: since tax increases the price of an item you add it to the 100% and multiply by the $18. So 106% times $18.