Answer:
The following solution is incorrect. The correct value of x is 7.
Step-by-step explanation:

Distribute 3 to (4x-15). When distributing, the value outside parentheses is multiplied to all the numbers inside the parentheses. Since the 3 was only multiplied to 4x, the solution is wrong.

Add 45 to both sides.

Divide by 12 from both sides.

I have attached an image showing the graph of the function.
Answer:
Zeros are x = $15 and x = $70 and they are the prices at which the woodworker will neither loss nor gain money.
Step-by-step explanation:
First of all, the zeros of a function f(x) are defined as the values of x where f(x) = 0. That is the points where the graph curve touches the x-axis.
Now, from the attached graph, when we locate the point that the curve touches the x-axis, it's at x = 15 and at x = 70.
This means that f(x) = 0 at x = 15 and at x = 70.
Now, from the graph; f(x) is the profit function. So when f(x) = 0, it means there is zero profit which implies no gain and no loss.
Thus, we can conclude that the prices at which the woodworker will neither loss nor gain money is when the price is; x = $15 and x = $70
Answer:
the answer to the first one is 118 the value of x is 113
Step-by-step explanation:
SOMEONE DELETED MY ORIGINAL ANSWER
The answer is x = 10, y = 10.
Step 1: rearrange the second equation for y.
Step 2: substitute y from the second equation into the first equation.
Step 3. Calculate y.
Step 1.
<span>The second equation is: 6x + 3y = 90
Divide both sides of the equation by 3:
(6x + 3y)/3 = 90/3
6x/3 + 3y/3 = 30
2x + y = 30
Rearrange the equation:
y = 30 - 2x
Step 2.
</span>Substitute y from the second equation (y = 30 - 2x) into the first equation:
<span>15x + 9y = 240
15x + 9(30 - 2x) = 240
15x + 270 - 18x = 240
15x - 18x = 240 - 270
-3x = -30
x = -30/-3
x = 10
Step 3.
Since </span>y = 30 - 2x and x = 10, then:
y = 30 - 2 * 10
y = 30 - 20
y = 10