Answer:
In a system, the substitution method is one of the 3 main ways to solve a system and can be very efficient at times.
<u>Skills needed: Systems, Algebra</u>
Step-by-step explanation:
1) Let's say we are given two equations below:

We can use substitution here by substituting in for
in the second equation. This means we put in
for
in the 2nd equation so we only have
variables in the equation, allowing us to solve for
.
2) Solving it out:

We essentially substitute in that value as seen in step 1. Steps 2 and 3 are just simplifying the left side and allowing for us to solve. Step 4 is where we divide by -16 on both sides to solve for x. Step 5 and 6 show us solving for y using the value for x. We get 
Answer:
24ft is the length of the shadow of the telephone pole
Step-by-step explanation:
Well first what I did was divide 15 by 4 which equaled to 3.75, after that the question said that the telephone pole was now 90 feet tall so I just had to divide 90 by 3.75 and then 24 ft long was the final answer. I hope that helps
Answer:
let the daughter age be x
let mother age be 3x
Step-by-step explanation:
x+3x= 80
4x = 80
x= 80\4
x=20
daughter age is 20
mather age= 80 -20
= 60
daughter age 20
mother age 60
Step-by-step explanation:
the area of a triangle is always
baseline × height / 2
where baseline and height are perpendicular (at a 90° angle) to each other.
so, in our case the area is
7 × 2 / 2 = 7 × 1 = 7 units²
Answer:
4:5
Step-by-step explanation:
You can divide two to each number.
8 divided by 2 equals 4.
10 divided by 2 equals 5.