Proof by contradiction is a form of proof that establishes the truth or the validity of a proposition, by showing that assuming the proposition to be false leads to a contradiction. I googled this so it may not be correct
The solution of (3,13) means you need to create two lines that satisfy x = 3 and y = 13
The two lines can be anything as long as they give this solution
For example, if you wrote x + y = 16 (you know their values already)
Then write another y - x = 10
From here you have your equations, turn them into the f(x) form.
x + y = 16 can be turned into y = 16 - x which is f(x)=16-x
y-x = 10 can be turned into y = 10 + x which is g(x)=10 + x
Unhurried
Relaxed
Easy lagging
Eisurely
1. <span>-0.9x+2.8=4.1
First subtract 2.8 from both sides.
-0.9x = 1.3
Now divide both sides by -0.9.
x = -1.4444..
This can be rounded to -1.44
</span><span>c) -1.44
2. Jordan has 650 pennies. He'll give 85 to his brother and split the rest with his sister.
</span>d) 85+2x=650
<h3>
Answer: True</h3>
Explanation:
Technically you could isolate any variable you wanted, from either equation. However, convention is to pick the variable in which isolating it is easiest, and most efficient.
The key thing to look for is if there's a coefficient of 1. This is found in the second equation for the y term. Think of -4x+y = -13 as -4x+1y = -13. Due to the coefficient of 1, when solving for y we won't involve messy fractions.
If you were to solve for y, then you'd get y = 4x-13, which is then plugged in (aka substituted) into the first equation. That allows you to solve for x. Once you know x, you can determine y.