SOLUTION: Create coefficient matrix and augmented matrix for the following: Given the formula y= a(t^2) + bt + c, we can find the height, y, of an item thrown into the air. If an item is th

Algebra.Com
Question 908650: Create coefficient matrix and augmented matrix for the following:
Given the formula y= a(t^2) + bt + c, we can find the height, y, of an item thrown into the air. If an item is thrown and is at height, y= 23/4 at time, t= 1/2 and is at y= 7 at t= 1, and is at y= 2 at t= 2, solve for the coefficients a, b and c.

Found 2 solutions by ewatrrr, richwmiller:
Answer by ewatrrr(24785)   (Show Source): You can put this solution on YOUR website!
1/4a + b/2 + c = 23/4
.....
4a + 2b + c = 2
a + b + c = 7 Subtract 2nd from 1st EQ
3a + b = -5
..........
a + b + c = 7
1/4a + b/2 + c = 23/4 Subtract 2nd from 1st EQ
3/4a= -5/4
..............
3a + b = -5
3/4a + 1/2b = -5/4|multiplying thru by -2 to eliminate the b variable by adding the Eqs
3/2a = = -15/2
a = -5, b = 10 and c = 2

Answer by richwmiller(17219)   (Show Source): You can put this solution on YOUR website!
coefficient matrix
.25,.5,1
4,2,1
1,1,1
coefficient matrix

augmented decimals
.25,.5,1|5.75
4,2,1|2
1,1,1|7

augmented fractions

.25,.5,1,5.75
4,2,1,2
1,1,1,7
divide row 1 by 0.25
1,2,4,23
4,2,1,2
1,1,1,7
add down (-4) *row 1 to row 2
1,2,4,23
0,-6,-15,-90
1,1,1,7
add down (-1) *row 1 to row 3
1,2,4,23
0,-6,-15,-90
0,-1,-3,-16
divide row 2 by -6
1,2,4,23
0,1,-15/-6,15
0,-1,-3,-16
add down (1) *row 2 to row 3
1,2,4,23
0,1,5/2,15
0,0,-1/2,-1
divide row 3 by -1/2
1,2,4,23
0,1,5/2,15
0,0,1,2
We now have the value for the last variable.
We will work our way up and get the other solutions.
add up (-5/2) *row 3 to row 2
1,2,4,23
0,1,0,10
0,0,1,2
add up (-4) *row 3 to row 1
1,2,0,15
0,1,0,10
0,0,1,2
add up (-2) *row 2 to row 1
1,0,0,-5
0,1,0,10
0,0,1,2
final
1,0,0,-5
0,1,0,10
0,0,1,2
"-5","10","2"
(-5,10,2)

RELATED QUESTIONS

Solve the linear system by row-reducing the corresponding augmented matrix: -w+x-z=14... (answered by Edwin McCravy)
3𝑥 − 5𝑦 + 2𝑧 = 2 2𝑥 − 𝑦 + 3𝑧 = 3 𝑥 + 4𝑦 + 7𝑧 = 4... (answered by ikleyn)
Write the coefficient matrix and the augmented matrix of the given system of linear... (answered by Edwin McCravy)
2. You are given the following system of linear equations: 3x 2y + z = 2 -x + y = 3 (answered by Fombitz)
Create coefficient matrix and augmented matrix for the following: A total of $25,000 is... (answered by ewatrrr)
A Matrix is given. a) Determine whether the matrix is in row-echelon form. b) Determine... (answered by Edwin McCravy)
Write the coefficient matrix and the augmented matrix of the given system of linear... (answered by ikleyn)
19. Give the solution for a system with the augmented matrix shown below [1 0: 2] [0... (answered by Edwin McCravy)
Find all values of k for which the given the augmented matrix corresponds to a consistent (answered by MathLover1,math_tutor2020)