Use subtitution method to solve the problem.
First, change y to the value of x in order to find the exact value of x.
x + y = 4
y = 4 - x
Second, subtitute y with 4 - x from the first equation
y = -x² + 2x + 4
4 - x = -x² + 2x + 4
move all terms to the left side
x² - 2x - x + 4 - 4 = 0
x² - 3x = 0
x(x - 3) = 0
x = 0 or x = 3
Third, now we have 2 values of x. Find the value of y for each of x
For x = 0
y = 4 - x
y = 4 - 0
y = 4
For x = 3
y = 4 - x
y = 4 - 3
y = 1
The solution is (0,4) and (3,1). The answer is option b
We are given 4 points.




Using this, we can make an equation.

I got
by using the slope formula.



So the equation we have is 
Now, we can solve for how much peanut butter is used to make 25 packages by plugging in 25 for
, which is the number of cracker packages.


We need to use
teaspoons of peanut butter to make 25 packages of crackers.
Hope this helps.
頑張って!
Since we know that the 38 is being bisected (which we can tell by the fact that the line hits it perpendicularly), we know that from the intersection to the edge of the circle is 19. From this we can create a right triangle in which the legs are 10 and 19 and the hypotenuse is a radius of the circle. Since x is also a radius of the circle, all we have to do is use that information to find the hypotenuse using the Pythagorean Theorem and we have x.
Pythagorean Theorem

+

=


+

=

100 + 361 =

461 =

x =

or about 21.47
Answer: She mixed up the slope and y-intercept when she wrote the equation in step 3.
Step-by- explanation:
Hope this helps :)