Answer:

Step-by-step explanation:
So we have the system:

If we isolate the x-variable in the first equation:

Subtract 2y from both sides:

Divide both sides by -1:

Therefore, we would substitute the above into the second equation:

The answer is 2y+6
Further notes:
To solve for the system, distribute:

Simplify:

Subtract:

Divide:

Now, substitute this value back into the isolated equation:

Answer:
Multiply by 3 on both sides of the equation.
2.78 × 3 = 8.34, so t = 8.34.
Substitute 8.34 for t to check the solution.
Step-by-step explanation:
To solve the equation = 2.78
we will use the steps below to solve this equation;
First, multiply by 3 on both-side of the equation. That is;
× 3= 2.78 × 3
On the left hand side of the equation 3 will cancel-out 3, leaving us with just t while 3 will be multiply by 2.77 on the right-hand side of the equation to give 8.34
t = 8.34
we can further substitute 8.34 for t to check the correctness of the solution
that is;
= 2.78
R
Answer: Andrew = 20
Jimmy = 25
Richard = 100
Step-by-step explanation:
Let the number of Andrew's comic books be y.
Jimmy has five more comic books than Andrew. This means Jimmy has: y+5
Richard has four times as many comic book as jimmy. This means Richard has: 4(y+5) = 4y + 20
Since there are 145 comic books together. This can be rewritten as:
y + (y+5) + (4y+20) = 145
6y+25 = 145
6y = 145 - 25
y = 120/6
y = 20
Andrew has 20 comic books
Jimmy has five more comic books than Andrew. Jimmy has: 20+5 = 25
Richard has: 4y + 20 = 4(20) + 20 = 100