Answer:
I do not fully know your question, but your slope is m=1, your y-intercept is 12, and your x-intercept would be (-12,0). I hope this helps. Try to reconstruct your question next time.
For this case, the first thing we must do is define variables.
We have then:
x: Maggie's age
y: Age of Maggie's brother
We write the system of equations that models the problem.
We have then:

We solve the system of equations.
For this, we use substitution:

From here, we clear the value of x:


Answer:
Maggie is 9 years old
In order to answer this question, we must break this mathematical expression up into a series of mathematical operations (exponent, multiplication,division, addition, and/or subtraction):
"4 times a number" - The word "times" implies that we have to multiply 4 by an unknown number. We can simply label this unknown number as x.
"cubed" - In order to "cube" a number, we must raise it to the third power, or have an exponent of 3. Our unknown number of x now becomes x3 because we raised it to the third power.
"decreased by 7" - The word "decreased" implies that we must subtract 7 from the product of 4 multiplied by x3
With all of the information we now have, we can form an algebraic expression for this problem.
"4 times a number cubed decreased by 3" now becomes:
4x3 - 7
Step-by-step explanation:
not sure about last question but...did it with all my will..