Answer:
0.80
Step-by-step explanation:
Khan told me
Option A
The solution is 
<em><u>Solution:</u></em>
<em><u>Given system of equations are:</u></em>
3x + 6y = 1 ------ eqn 1
x - 4y = 1 ------ eqn 2
We have to find solution to system of equations
We can use substitution method
From eqn 2,
x = 1 + 4y -------- eqn 3
Substitute eqn 3 in eqn 1
3(1 + 4y) + 6y = 1
3 + 12y + 6y = 1
18y = 1 - 3
18y = -2
Divide both sides by 18

Substitute the above value of y in eqn 3

Thus solution is 
Let's simplify step-by-step.<span><span><span><span>8.9x</span>−5</span>−<span>6.8x</span></span>+8</span><span>=<span><span><span><span><span><span>8.9x</span>+</span>−5</span>+</span>−<span>6.8x</span></span>+<span>8
</span></span></span>Combine Like Terms:<span>=<span><span><span><span>8.9x</span>+<span>−5</span></span>+<span>−<span>6.8x</span></span></span>+8</span></span><span>=<span><span>(<span><span>8.9x</span>+<span>−<span>6.8x</span></span></span>)</span>+<span>(<span><span>−5</span>+8</span>)</span></span></span><span>=<span><span>2.1x</span>+<span>3
The simplified answer is </span></span></span><span><span>2.1x</span>+<span>3</span></span>
The sum of 15 and r.
Sum is the term used in verbal addition problems.
This is an expression therefore, you do not state what it equals. We no this because there is no equals sign.