a. for each decrease of 3 in y,an increase of 1 in x.
y=mx+b=-3/1 m +b
and b..
1=-3(-3)+b
b=8
b. y=ax^2+bx+c
put in three different data points, solve for a, b, c.
15.
Do the data in the table represent a linear function? If so, write a rule for the function.
x –3 –2 –1 0 1
y 1 –2 –5 –8 –11
(1 point)
yes; y = –3x – 8
yes; y = 1/3x – 8
yes; y = 1/3x + 8
yes; y = 3x + 8
16.
Write a quadratic rule for the data in the table.
x –1 0 1 2 3
y 4 5 4 1 –4
(1 point)
y = –2x^2 + 5
y = –x^2 + 5
y = x^2 – 5
y = x^2 + 5
Can you please also explain how to solve this?
2 answers
for the quadratic, note that
f(-1) = f(1) = 4
That means the vertex lies on the line x=0.
y = a(x-0)^2 + c
or,
y = ax^2+5
Now use one other point to get a:
1 = 4a+5
a = -1
y = -x^2+5
f(-1) = f(1) = 4
That means the vertex lies on the line x=0.
y = a(x-0)^2 + c
or,
y = ax^2+5
Now use one other point to get a:
1 = 4a+5
a = -1
y = -x^2+5
0 answers