X=y+3
<span>-5x-4y=<span>30
-------------------
Substitute y + 3 for x in </span></span>-5x-4y=30
<span><span>-5<span>(y+3)-</span></span>4y</span>=<span>30
</span>-9y-15=<span>30
</span>----------------------------
Add 15 to each side
<span><span>-9y-15</span>+15</span>=<span>30+<span>15
-9y = 45
</span></span>-----------------------------------
Divide each side by -9
-9y ÷ -9 = 45 ÷ -9
y = -5
Now we solve for x
====================================================================
Substitute -5 for y in x = y + 3
x=-<span><span>5</span>+<span>3
</span></span>x = -2
----------------------
(-2,-5) is your answer
Answer:
Inverse property of addition
Step-by-step explanation:
When you add two opposite numbers (4/5 is the opposite of [-4/5]) the answer is always zero.
Answer:
, x = 6 ton
Step-by-step explanation:
The truck can be filled with a total of 20 ton.
There are already 14 ton inside the truck, so if we call x the weight of goods that we can still add into the truck, we know that (x+14) must be equal at most at 20. Therefore, the inequality becomes:

Solving it, we find

which means that the most amount of goods that could be added to the truck is 6 tons.
The negation isn't always true, as you can be unhappy while also not being hungry.