The 4 sides of a square are equal in length, so if the perimeter is 20ft that means each side would have to be 5ft, (20/4 = 5). If you increase the length by 2ft, one of the sides would now become 7ft (5+2 = 7). If you decrease the length of the other side by 1ft, the length would now be 4ft (5-1=4). Now to find the area, all you have to do is length * width. So you would do 7ft*4ft which is 28ft squared.

4 0

3 years ago

Prove that 1/sin^2A -1/tan^2A= 1

Vika [28.1K]

Answer:

Step-by-step explanation:

$LHS =\dfrac{1}{Sin^{2} \ A }-\dfrac{1}{Tan^{2} \ A }\\\\\\ = \dfrac{1}{sin^{2} \ A}- \dfrac{1}{\dfrac{Sin^{2} \ A}{Cos^{2} \ A}}\\\\\\= \dfrac{1}{sin^{2} \ A } - \dfrac{Cos^{2} \ A}{Sin^{2} \ A}\\\\\\= \dfrac{1-Cos^{2} \ A}{Sin^{2} \ A}\\\\\\= \dfrac{Sin^{2} \ A}{Sin^{2} \ A}\\\\\\= 1 = \ RHS$

Hint: 1 - Cos² A = Sin² A

4 0

2 years ago

Triangle ABC with A at 0 comma 0, B at 2 comma 4 and C at 0 comma 2, the measure of angle C is 127 degrees, and the measure of a

Nikolay [14]

Answer:

The Answer is B.

Step-by-step explanation:

I got it right on my test

For further evidence here is a picture of the answer

6 0

2 years ago

A t-shirt increased in price by 1/4. After the increase it was £20. What was the original price of the t-shirt?

Licemer1 [7]

Answer:

£16

the t-shirt increased by 0.25. let's convert that to percentage

therefore it increased by 25%

By using cross multiplication we can write as follows:

125%=£20

100%=£ x

(100×20)/125= £16

8 0

2 years ago