Answer: 82 sq. units .
Step-by-step explanation:
Let A (9, −1), B (−1, 7), C(−5, 2), D(5, −6) are the vertices of rectangle.
Then we plot them on graph ( as provided in attachment)
Length = AB units [By distance formula :
]
units
Width = BC = units
Area = length x width
=
Hence, the area of the rectangle is 82 sq. units .
Expression consists of numbers, variables, and mathematical operations. The expression f(w)=5(w+4) is equal to f(9)=5(9)+20.
<h3>What is an Expression?</h3>In mathematics, an expression is defined as a set of numbers, variables, and mathematical operations formed according to rules dependent on the context.
The expression is given to you is,
Now, if we solve the expression it can be written as,
substituting the value of w, we will get,
Hence, the expression f(w)=5(w+4) is equal to f(9)=5(9)+20.
Learn more about Expression: