1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
Elan Coil [88]
3 years ago
7

Select the x-coordinate of the vertex of the parabola defined by the function f(x)=-9x^2+7x+8

Mathematics
2 answers:
mote1985 [20]3 years ago
7 0
x_v=-\frac{b}{2a}\\
x_v=-\frac{7}{2\cdot(-9)}\\
x_v=\frac{7}{18}\\
Verdich [7]3 years ago
4 0
f(x)=-9x^2+7x+8\\\\a=-9;\ b=7;\ c=8\\\\x_{vertex}=\frac{-b}{2a}\\\\x_{vertex}=\frac{-7}{2\cdot(-9)}=\frac{-7}{-18}=\frac{7}{18}
You might be interested in
Short sleeve t-shirts cost $10 and long sleeve t-shirts cost $15. If the t-shirt shop made $485 selling 38 total t-shirts, how m
BartSMP [9]

Answer:

The t-shirt shop sold 21 long sleeve shirts and 17 short sleeve shirts.

Step-by-step explanation:

To solve this problem, we should create a system of equations.  Let's let short sleeve t-shirts be represented by the variable s and long sleeve t-shirts be represented by the variable l.  

We know that the shop sold 38 total shirts, or in other words, the amount of long sleeve and short sleeve shirts combined is 38.  If we write this as an equation, we get: s + l = 38.

We can make another equation with the prices of the shirts.  If we take each type of shirt and multiply each price by the number sold and add them together, we should get the shop's total profits.  Represented as an equation, this is: 10s + 15l = 485.

Now that we have two equations, we should try to solve the system.  In this case, it is easiest to use substitution, so we are going to rewrite the first equation in terms of one variable.

s + l = 38

s = 38 - l

If we substitute this equivalent value for the variable s into the second equation, we get:

10s + 15l = 485

10(38 - l) + 15l = 485

Now we have an equation that only has one variable, so we can simplify both sides and then isolate the variable.

380 - 10l + 15l = 485

380 + 5l = 485

5l = 105

l = 21

Now, we can substitute this value for l back into the first equation to solve for the variable s.

s + l = 38

s + 21 = 38

s = 17

Therefore, the t-shirt shop sold 21 long sleeve shirts and 17 short sleeve shirts.

Hope this helps!

5 0
4 years ago
A local hamburger shop sold a combined total of 617 hamburgers and cheeseburgers on Wednesday. There were 67 more cheeseburgers
Assoli18 [71]

Answer:

check the picture

Step-by-step explanation:

I hope you get it

5 0
3 years ago
The tens digit is three less than the units digit. If the digits are reversed, the sum of the reversed number and the original n
muminat

Answer:

Original number is 47

Step-by-step explanation:

Given: The tens digit is three less than the units digit. If the digits are reversed, the sum of the reversed number and the original number is 121.

To find: the original number

Solution:

Let x denotes digit at ones place.

As the tens digit is three less than the units digit,

Digit at tens place = x-3

Original number = 10(x-3)+x=11x-30

When digits are reversed,

Reversed number = 10x+(x-3)=11x-3

As the sum of the reversed number and the original number is 121,

11x-30+11x-3=121\\22x-33=121\\22x=154\\x=\frac{154}{22}\\=7

So,

original number = 11x-30=11(7)-30=77-30=47

8 0
3 years ago
Alternate interior angles. if you are good at that help ​
mamaluj [8]

Answer:

hi

Step-by-step explanation:

i think so,

(5x-54)⁰=(3x+16)⁰

5x-3x=16+54

2x=70

x=35⁰

3x+16=3×35+16=121

5x-54=5×35-54=121

hope it helps

have a nice day

8 0
3 years ago
Read 2 more answers
find the value of cos theta, if sin theta= 1/2; 0 degrees greater than or equal to theta < 90 degrees
vagabundo [1.1K]

Answer:

Step-by-step explanation:

According to the ratios table, if

sin theta = 1/2

Then theta = 30°

Cos theta = cos 30° =root 3 /2

6 0
3 years ago
Read 2 more answers
Other questions:
  • Are 2/5 and 6/10 are eqivalent
    5·2 answers
  • Which measurement is NOT equivalent to the others? *
    12·1 answer
  • What is 18 X 19 i cants figure it out
    7·2 answers
  • When rounded to the nearest tenth, a puppy has the weight of 8.1 pounds. which of these could be the actual weight in pounds?
    15·2 answers
  • 10 POINTS??!! +++ HELP ME ASAP
    5·2 answers
  • How do you solve 2 2/5 divided by 1/12
    6·2 answers
  • Can anyone please help me with this with an explanation
    5·2 answers
  • If the longest side of a triangle is 12 inches, what must be true about the lengths of the remaining sides?
    12·1 answer
  • Ind g(x), where g(x) is the translation 5 units right of f(x) = x.
    12·1 answer
  • Jon ran 4 miles in 35<br> minutes. How long did it<br> take him to run a mile
    11·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!