Answer: 9 elm trees were removed.
Step-by-step explanation:
Let x represent the number of elm trees removed.
The total number of elm trees in the park is 22. Elm leaf beetles have been attacking the trees. After removing several of the diseased trees, there are 13 healthy elm trees left. The equation to find the number of elm trees that were removed would be
x + 13 = 22
Subtracting 13 from the left hand side and the right hand side of the equation, it becomes
x + 13 - 13 = 22 - 13
x = 9
It's already in simplest form
Answer:
y=8x-67
Step-by-step explanation:
So the question is what is the equation for the following two coordinate points?
Well to start off what is the formula? The formula is called the linear equation. Which is y=mx+b. What does these letters or "variables" mean or represent?! Welp, m stands for the slope, which is "Δy over Δx." Some people call say "the change of y over x." I call it the rise over run. So it is saying y over x. The b in the linear equation is the y-intercept. The y-intercept is when the line crosses the y-axis.
With that being said, let's find the slope. But how? Well with the Δy over Δx. The formula is y₂-y₁ over x₂-x₁. With the two coordinate points we can label them.
y₂=5
y₁=(-11)
x₂=9
x₁= 7
Now let set it up into the equation of y over x
Slope = <u> 5- (-11) </u> = <u> 5 + 11 </u> = <u> 16 </u> = 8
9-7 9-7 2
So we now have the slope! Which is 8! So put that into the linear equation!
y=8x+b
Next, we need to find b, the y-intercept! How do we do that well, we can figure it out by one of the coordinate points! Let use the (7, -11) point for example! Remember, x= 7 and y= (-11)
(-11) = 8(7) + b
(-11) = 56 + b
<u>-56 -56</u>
-67 = b
We now have b, which is negative 67! So we need to put all the information we have found into the linear equation!
y=8x-67
