Answer:
Step-by-step explanation:
sorry i was late to answer
for 3 you have to do 7(3t-4)=21t-28
for 3b its
21t-28=56
21t=56+28
21t=84
t=4
Part (a): Expression for the area of the rectangle is (3t-4)(7).
Part (b): The value of t is 4.
A rectangle is one of the types of quadrilaterals in which all four angles are right angles or equal to 90 degrees. It is four-sided polygon in which the opposite sides are parallel and equal to each other.
For the given situation,
The diagram shows the rectangle.
The length of the rectangle,l = 3t - 4
The breadth of the rectangle,b = 7
The formula of area of rectangle, [tex]A = (l)(b)[/tex]
Part (a):
An expression for the area of the rectangle,
[tex]A=(3t-4)(7)[/tex]
Part (b):
The area of the rectangle, A = 56 sq.cm
⇒ [tex]56=(3t-4)(7)[/tex]
⇒ [tex]56=21t-28[/tex]
⇒ [tex]21t=56+28[/tex]
⇒ [tex]21t=84[/tex]
⇒ [tex]t=\frac{84}{21}[/tex]
⇒ [tex]t=4[/tex]
Hence we can conclude that
Part (a): Expression for the area of the rectangle is (3t-4)(7).
Part (b): The value of t is 4.
Learn more about the rectangles here
brainly.com/question/12019874
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