Answer:
See explanation
Step-by-step explanation:
Let x be the number of spade shovels, y -the number of flat shovels and z - the number of square showels sold that day.
The store keeps an inventory of 80 shovels, then
x+y+z=80
The store always buy twice as many spade shovels as square, so
x=2z
The total cost of all shovels is
16x+9.60y+12.80z=1,072
a) The system of three equations is

b) In matrix form this is

c) The determinant is

d) Find three determinants:



So,

e) If the store doubled all prices and inventory, then the new matrix is

Answer:
24.5
Step-by-step explanation:
When you round it you get 25. (sorry if im wrong) :(
Is "ab" an angle? If so, can you try to repost the picture because I cannot see anything so it's hard to try and help you.
Answer:
-2
Step-by-step explanation:
Replace x with -1
(-1)2 - (-1) - 1
-2 + 1 - 1
-2