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
lianna [129]
3 years ago
11

The parabola y=ax^2+bx-10 passes through the points (4.5,8) and (-2.5, 15). Determine the values of a and b

Mathematics
1 answer:
yuradex [85]3 years ago
6 0
y=ax^2+bx-10 \\ \\
(4.5,8) \\
8=a \times 4.5^2 + b \times 4.5-10 \\
8=20.25a+4.5b-10 \ \ \ |+10 \\
18=20.25a+4.5b \\ \\
(-2.5,15) \\
15=a \times (-2.5)^2+b \times (-2.5)-10 \\
15=6.25a-2.5b-10 \ \ \ |+10 \\
25=6.25a-2.5b

The system of equations:
18=20.25a+4.5b \ \ \ |\times 5 \\
25=6.25a-2.5b \ \ \ |\times 9 \\ \\
90=101.25a+22.5b \\
\underline{225=56.25a-22.5b} \\
90+225=101.25a+56.25a \\
315=157.5a \ \ \ |\div 157.5 \\
a=2 \\ \\
25=6.25a-2.5b \\
25=6.25 \times 2-2.5b \\
25=12.5 -2.5b \ \ \ |-12.5 \\
12.5=-2.5b \ \ \ |\div (-2.5) \\
b=-5 \\ \\
\boxed{a=2} \\ \boxed{b=-5} \\ \boxed{y=2x^2-5x-10}
You might be interested in
WILL MARK YOU BRAINLIEST
Juli2301 [7.4K]
We know that the sum of all angle measures in a trapezoid is 360* (* means degrees)

Therefore we can construct the equation
(X+28)+(x)+(4x-14)+(4x-14)= 360

Now add like terms

10x = 360

And divide by the coefficient of X (aka 10)

X= 36
7 0
3 years ago
What is the equation of the line in the slope intercept form
Grace [21]

Answer:

<em>Equation of line; y = - 6x</em>

Step-by-step explanation:

As we can see from this graph, point ( 0, 0 ) lying on this graph intersects the y - axis such that it forms a y - intercept of 0;

At the same time we can note that the change in y / change in x, in other words the slope, differs by a rise of 6 / run of - 1, 6 / - 1 being a slope of - 6;

If this equation is in slope - intercept form ⇒

y = a * x + b, where a ⇒ slope, and b ⇒ y - intercept,

<em>Equation of line; y = - 6x</em>

7 0
2 years ago
Read 2 more answers
Identify the factors of the function y = 6x2 – 9x
Sindrei [870]

Answer:

3x(2x - 3)

Step-by-step explanation:

Given

y = 6x² - 9x ← factor out 3x from each term

  = 3x(2x - 3)

6 0
3 years ago
How do you do this problem?
Burka [1]

Let area of triangle AEC = x

Area of triangle BAC = 1/2 * 15 * 12 = 90

Area of triangle DCA = 1/2 * 15 * 6 = 45

90 = p + x and

45 = q + x Subtracting the 2 equations:-

90 - 45 = p - q

Answer p - q = 45

7 0
2 years ago
Read 2 more answers
A Square was altered so that one side is increased by 9 inches in the other side is decreased by 2 inches.The area of the result
LekaFEV [45]

Let s represent the length of any one side of the original square.  The longer side of the resulting rectangle is s + 9 and the shorter side s - 2.

The area of this rectangle is (s+9)(s-2) = 60 in^2.

This is a quadratic equation and can be solved using various methods.  Let's rewrite this equation in standard form:  s^2 + 7s - 18 = 60, or:

s^2 + 7s - 78 = 0.  This factors as follows:  (s+13)(s-6)=0, so that s = -13 and s= 6.  Discard s = -13, since the side length cannot be negative.  Then s = 6, and the area of the original square was 36 in^2.

4 0
2 years ago
Other questions:
  • 1.Which fraction is the ratio expressed in simplest form?
    10·1 answer
  • What is (10/3) squared?
    10·2 answers
  • The circumstances is 6,562.6mm what is the diameter of the target
    9·1 answer
  • Which points on the graph represent values that could
    15·2 answers
  • Please help due today!!!
    12·1 answer
  • A young sumo wrestler decided to go on a special high-protein diet to gain weight rapidly. He started at 90 9090 kilograms and g
    12·1 answer
  • 11(p-3)=5(p+3) really need an answer please hahaha
    8·2 answers
  • First to answer gets brainleist! and 15-20 points ! ! i only need answers no step by step
    5·1 answer
  • PLEASE ANSWER THIS CORRECTLY!!!<br> please don't take this as an advantage this is serious work
    7·2 answers
  • A state offers specialty license plates that contain 5 numbers followed by 2 letters. License plates are assigned randomly. All
    12·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!