Answer:
Keisha bought 3 sandwiches and 5 lemonades.
Equations: x + y = 8 2x + y = 11
Step-by-step explanation:
To solve a problem with two variables, you need to set up a system of equations comparing the two variables and solve using either substitution or elimination. If 'x' represents the number of sandwiches and 'y' represents the number of lemonades, then x + y = 8 because they bought a total of 8 items. Also, the cost of each item is given as well as the total amount of money spent. So, our second equation is: 2x + y = 11. We can use inverse operations to solve for 'y' in the first equation: x + y - x = 8 - x which simplifies to: y = 8 - x. We can then use this expression to substitute in for the variable 'y' in the second equation: 2x + 8 - x = 11.
Combine like terms: x + 8 = 11
Inverse Operations: x +8 - 8 = 11 - 8
Solve: x = 3, so Keisha bought 3 sandwiches
Solve for y: y = 8 - 3 = 5, so Keisha bought 5 lemonades
Step-by-step explanation:
Let's say b is the rate of the boat in still water, and c is the rate of the current.
Distance = rate × time
Going upstream:
100 = (b − c) (5)
20 = b − c
Going downstream:
100 = (b + c) (2)
50 = b + c
Solve the system of equations using substitution or elimination. Using elimination, add the equations together:
70 = 2b
b = 35
c = 15
The boat's speed is 35 km/h, and the current's speed is 15 km/h.
Answer:
P, M, N and C are coplanar, because they are on the same plane.
Noncollinear, because they are not on the same line.
Hope this helps :)
Answer:
undefined
Step-by-step explanation:
First expression
=> 3 x 3 x 3 x 3 x 3 – In this expression, we multiplied 3 5 times and the product is 243
Second expression
=> 3 ^ 5 , in where ^ read as raised to the power. , the product is also 243
Third expression
=> 3^2 x 3 ^3
=> (3 x 3) x (3 x 3 x 3)
=> 9 x 27, the product is also equals to 243.
