Answer: all of them
Step-by-step explanation: im smart
If you are working with time or days, you can't put in a negative value because if you are doing an experiment, you can't go back in time to do that experiment to gather data. (Time for the most part considered to be an input value so that's why I used it as an example.)
15, 18, 21
i don't know the other one, sorry
Solve <span>4x − 3y = 3 and 5x − 4y = 3
Step 1: Solve for x in 4x-3y=3:
4x-3y=3
4x-3y+3y=3+3y [Add 3y to both sides]
4x=3y+3
</span>

[Divide both sides by 4]
x=

Step 2: Substitute

<span> for x in 5x-4y=3
5x-4y=3
5(</span>

<span>)-4y=3
</span>


[Subtract

to both sides]


[Divide both sides by

]
<span>y = 3
Step 3: Substitute 3 for y in x = </span>


x = 3
Answer:
Answer:
28+66+86=180
180=180
Step-by-step explanation:
Since there is a triangle and the 3 measures from the angles we can find the value of x using the hint given that the sum of the interior angles must be 180°
Write the equation
\begin{gathered}x+(2x+10)+(3x+2)=180\\\end{gathered}
x+(2x+10)+(3x+2)=180
Simplify left side of the equation
\begin{gathered}6x+12=180\\\end{gathered}
6x+12=180
Solve equation for x
\begin{gathered}6x=180-12\\6x=168\\x=28\end{gathered}
6x=180−12
6x=168
x=28
Replace x into the 3 angles and find their respectives values
\begin{gathered}A=x\\A=28\\\\B=2x+10\\B=2*28+10\\B=56+10\\B=66\\\\C=3x+2\\C=84+2\\C=86\end{gathered}
A=x
A=28
B=2x+10
B=2∗28+10
B=56+10
B=66
C=3x+2
C=84+2
C=86
Check if the answers are correct
\begin{gathered}28+66+86=180\\180=180\end{gathered}
28+66+86=180
180=180
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