SOLUTION: Using inverse matrix, solve the following problem:
A high school math department purchased brand A calculators
for $80 each and brand B calculators for $95 each. It purchased
Algebra ->
Matrices-and-determiminant
-> SOLUTION: Using inverse matrix, solve the following problem:
A high school math department purchased brand A calculators
for $80 each and brand B calculators for $95 each. It purchased
Log On
Question 230768: Using inverse matrix, solve the following problem:
A high school math department purchased brand A calculators
for $80 each and brand B calculators for $95 each. It purchased
a total of 20 calculators at a total cost of $1780. How many brand A
and brand B calculators did the department purchase? Answer by rfer(16322) (Show Source):
You can put this solution on YOUR website! a+b=20, a=20-b
80a+95b=1780
substitute
80(20-b)+95b=1780
1600-80b+95b=1780
15b=180
b=12=$1140
a=8=$640
(