HELP PLEASE ANYONE please​

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Step-by-step explanation:

area of a rectangle is length x width

So, for example for the house you would do 30 x 40, which is 1200

Then work out using the same equation for the Backyard and add it to 1200 to find your total area

v: l•w•h÷2.

v: 20•6•8 ÷2

v: 960÷2

v: 480

= 5

step-by-step explanation:

to find the 15th term substitute n = 15 into the nth term formula

= (- 3 × 15 ) + 50 = - 45 + 50 = 5