1. If the area of a rectangular field is (21x2 - 7x) and one of its sides is 7x, what is its other side?
2. If a train travels (30a+ 15a - 10) kilometres in 10 hours, what is its average speed?
Answers
Step-by-step explanation:
ANSWER
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RECTANGLE
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A polygon with four sides whose -
Opposite sides are equal.
The sides meet at right angle . Therefore , all angles of a rectangle are 90°.
A.T.Q.
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Area of a rectangular field = 21x² - 7x m²
One side ( length ) = 7x
Therefore , breadth =
We know----
Area of rectangle = Length × Breadth
21x² - 7x = 7x × b
= > \: breadth \: = \: \frac{21 {x}^{2} - 7x }{7x} \\ \\ = > \: \frac{7x(3x - 1)}{7x(1)} \\ \\ = > breadth \: = 3x - 1 \: \: ans
Answer:
1. Length of rectangle = 7x
Area of rectangle = 21x² -7x
We know that
area of rectangle= Length*breadth
Thus, breadth =area÷ Length
= 21x² -7x / 7x
= (21x²/ 7x) - (7x/7x)e
= 3x -1
Therefore other side= 3x-1
2. Distance: 30a +15a -10 km
Time: 10 hours
Speed= Distance ÷ Time
= (30a +15a -10) /10
= (45a-10) /10
= (45a/10) - (10/10)
= (4.5a - 1) km/hr