Answer:
<em>Thus, the dimensions of the metal plate are 10 dm and 8 dm.</em>
Step-by-step explanation:
For a quadratic equation:

The sum of the roots is -b and the product is c. Note the leading coefficient is 1.
We know the perimeter of the rectangular metal plate is 36 dm and its area is 80 dm^2. Being L and W its dimensions, then:
P=2(L+W)=36
A=L.W=80
Note both formulas are closely related to the roots of the quadratic equation, we only need to adjust the data for the perimeter to be exactly the sum of L+W and not double of it.
Thus we use the semi perimeter instead as P/2=L+W=18
The quadratic equation is, then:

Factoring by finding two numbers that add up to 18 and have a product of 80:

The solutions to the equation are:
x=10, x=8
Thus, the dimensions of the metal plate are 10 dm and 8 dm.
Answer:
2.2 hr
Step-by-step explanation:
Let t = time
95t = distance of westbound train
105t = distance of eastbound train
95t + 105t = 440
200t = 440
t = 2.2 hr.
Men: 132
Women: 90
Children: 36
Total: 258
Answer:


Step-by-step explanation:
Given

Number of Girls : 0 ----> 1 -----> 2 ------->3
Number of Families: 112 -> 314 --> 382 ---> 192
Solving (a): At most one girl
From the table, the number of families with at most one girl is: 112 + 314
i.e.
Number of Girls : 0 ----> 1
Number of Families: 112 -> 314
So, we have:


The probability is then calculated as:



Solving (b): More girls
From the table, the number of families with more girl is: 382 + 192
i.e.
Number of Girls : -----> 2 ------->3
Number of Families: --> 382 ---> 192
So, we have:


The probability is then calculated as:



Answer:
is 21
Step-by-step explanation:
becuase 7-6 (the lCM) is 1 and 20 + 1 = 21