Answer:
k = 3.
Step-by-step explanation:
By the Factor Theorem. if x+a is a factor of f(x) then f(-a) = 0.
Here we use f(-1):
f(-1) = (-1)^3 + 2(-1) + k = 0
-1 - 2 + k = 0
k = 3.
Answer: Yes, the point (3,4) is a solution to the system.
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Proof of this:
Replace x with 3 and y with 4 in the first equation
x+y = 7
3+4 = 7
7 = 7
This confirms the first equation. Repeat for the second equation
x-2y = -5
3-2(4) = -5
3 - 8 = -5
-5 = -5
We get true equations for both when we plug in (x,y) = (3,4). This confirms it is a valid solution to the system of equations. It turns out it's the only solution to this system of equations. Visually, the two lines cross at the single location (3,4).
Answer:
6+15x
Step by step explanation:
Expansion
Answer:
t=+4.06
Step-by-step explanation:
when the baseball hits the ground, the height will be 0.
h=0we are given that h=−16t2+64t+4.
this means that the height is 0 when −16t2+64t+4=0.−16t2+64t+4=0divide both sides by 4:−4t2+16t+1=04=0−4t2+16t+1=0 can be solved using the quadratic formula:t=−b±√b2−4ac2a, where at2+bt+c=0.at2+bt+c=−4t2+16t+1a=−4,b=16,c=1t=−b+√b2−4ac2aor−b−√b2−4ac2a−b+√b2−4ac2a=−16+√272−8=−0.06..−b−√b2−4ac2a=−16−√272−8=4.06 (3s.f.)we have 2 values for t:−0.06 and 4.06.
since time cannot be negative, only the positive value can be taken.
this is 4.06, to 3 significant figures.the time taken is 4.06 seconds.
Answer: i've heard about it but i'm not too much into it