Answer:
1.25r+8=28
Step-by-step explanation:
Answer:
x = 149, cars and 51 motorcyles
Step-by-step explanation:
4x + 2(200-x) = 698
2x = 298 x = 149, cars and 51 motorcyles
Let's call the width of our rectangle and the length . We can say , since the length is equal to 4 cm greater than the width.
Also remember that the perimeter of a rectangle is the sum of two times the width and two times the length, or . To solve this problem, we can substitute in the information we know, as shown below:
Now, we can substitute in the width we found into the formula for length, which is :
The width of our rectangle is cm and the length of our rectangle is
For word problems, assign variables so you can express them into equations. For this problem, the unknown is the number of each animals. Let's assign x to the number of cows and y to the number of chickens. It is mentioned that there are a total of 28 animals. Therefore, we can formulate the first independent equation to be
x + y = 28 ---> eqn 1
Next, we know that the total number of legs are 74. Since each cow has 4 legs and each chicken has 2 legs, the second independent equation we could formulate is:
4x + 2y = 74 ---> eqn 2
Now, we have a system of linear equations. There are two unknowns and two independent equations. Thus, the system is solvable. Let's use the method of substituting to solve this. Rearrange eqn 1 such that x is a function of y. Let's denote this as eqn 1'.
x = 28 - y ---> eqn 1'
Substitute eqn 1' to eqn 2:
4(28 - y) + 2y = 74
112 - 4y + 2y = 74
-2y = 74 - 112
-2y = -38
y = -38/-2
y = 19
Therefore, there are 19 chickens. Now, we use y=19 to substitute to eqn 1:
x + 19 = 28
x = 28 - 19
x = 9
Therefore, there are 9 cows.