Answer:
<h3>B. -84</h3>
Step-by-step explanation:
Taking the determinant of the matrices we will have;
= 4x(5y) - 2x(3y)
= 20xy - 6xy
= 14xy
Given x = -2 and y = 3
Determinant = 14(-2)(3)
Determinant = -28*3
Determinant = -84
we will check each options
option-A:
For solving any equations , we always isolate variables on anyone side
For exp: x+7=1
so, this is TRUE
option-B:
For solving system of equations
For exp:
x-y=1
x+y=3
If we use addition , we could easily solve for x and y
so, this is TRUE
option-C:
We always solve problems using conventional method
we do not guess
so, this is FALSE
option-D:
We often reverse order of operation
For exp:
(x-2)^2-3=0
so, this is TRUE
option-E:
For linear equations , we always get one solution , infinite solutions or no solutions
so, this is FALSE
To determine the cost of each item, we need to set up equations. From the problem statement, we have three unknowns so we need three equations. We set up equations as follows:
let x cost of small pizzas
y cost of soda
z cost of salad
two small pizzas, a liter of soda, and a salad cost $14
2x + y + z = 14
one small pizza, a liter of soda, and three salads cost $15
x + y + 3z = 15
three small pizzas, a liter of soda, and two salads cost $22
3x + y + 2z = 22
Solving for x, y and z, we will have:
x = $ 5
y = $ 1
z = $ 3
Answer:
45/10, 4 3/5, 19/4
Step-by-step explanation:
19/4 = 4.75
45/10 = 4.5
4 3/5 = 23/5 = 4.6
4.75 > 4.6 > 4.5
Best of Luck!