Answer:
second one: -4x +6
third one: 4x - 16
fourth: 245x + 30
fifth: 81x - 21x
(last one) sixth: 1600x + 8x
( if this goes wrong then I did something else)
Answer:
Circumscribed circle: Around 80.95
Inscribed circle: Around 3.298
Step-by-step explanation:
Since C is a right angle, when the circle is circumscribed it will be an inscribed angle with a corresponding arc length of 2*90=180 degrees. This means that AB is the diameter of the circle. Since the cosine of an angle in a right triangle is equivalent to the length of the adjacent side divided by the length of the hypotenuse:

To find the area of the circumscribed circle:

To find the area of the inscribed circle, you need the length of AC, which you can find with the Pythagorean Theorem:

The area of the triangle is:

The semiperimeter of the triangle is:

The radius of the circle is therefore 
The area of the inscribed circle then is
.
Hope this helps!
PEMDAS states that the value in the parenthesis should be evaluated first:
4(5*6)
4(30)
After just multiply the value in the parenthesis by the number outside of the parenthesis:
120
I=PRT/100
1. Make R (rate) subject
R/100= I/PT
2. Substitute and calculate
r/100= i/pt
r/100= 40/400 × 1
(<em>4</em><em>0</em><em> </em><em>i</em><em>s</em><em> </em>from 440-400.<em>T</em><em>h</em><em>e</em><em> </em><em>i</em><em>n</em><em>t</em><em>e</em><em>r</em><em>e</em><em>s</em><em>t</em>)
r/100= 0.1
r/100×100= 0.1×100
r=10% (interest rate per year)
To confirm
I=PRT
I= 400×10/100×1
I= $40 (Interest)