Need with these questions! just 3 of them, it's very much appreciated : ) also if you could say how you figured them out that'd be a great as well

#1 part 1. 2(7/6w+w) (The formula is width of each side is added, then multiplied by 2.)

#1 part 2. 84.5 (You do 52/8, then you get 6.5 and times that by 3. You get 13. Then you do 13*6.5 and get 84.5) (You divide it by 8 because you know a rectangle has 2 sides longer than the other 2.)

#2. 16 ( Add lowest and highest temperature together, then divide by 2. 27-(-9)= 36. 36/2=16.)

#3 part 1. z - 4/3 = 7. (Just read the sentence. Its pretty obvious.)

#3 part 2. 8.333(Step by step solution :

Step 1 :

4
Simplify —
3
Equation at the end of step 1 :

4
(z - —) - 7 = 0
3
Step 2 :

Rewriting the whole as an Equivalent Fraction :

2.1 Subtracting a fraction from a whole

Rewrite the whole as a fraction using 3 as the denominator :

z z • 3
z = — = —————
1 3
Equivalent fraction : The fraction thus generated looks different but has the same value as the whole

Common denominator : The equivalent fraction and the other fraction involved in the calculation share the same denominator

Adding fractions that have a common denominator :

2.2 Adding up the two equivalent fractions
Add the two equivalent fractions which now have a common denominator

Combine the numerators together, put the sum or difference over the common denominator then reduce to lowest terms if possible:

z • 3 - (4) 3z - 4
——————————— = ——————
3 3
Equation at the end of step 2 :

(3z - 4)
———————— - 7 = 0
3
Step 3 :

Rewriting the whole as an Equivalent Fraction :

3.1 Subtracting a whole from a fraction

Rewrite the whole as a fraction using 3 as the denominator :

7 7 • 3
7 = — = —————
1 3
Adding fractions that have a common denominator :

3.2 Adding up the two equivalent fractions

(3z-4) - (7 • 3) 3z - 25
———————————————— = ———————
3 3
Equation at the end of step 3 :

3z - 25
——————— = 0
3
Step 4 :

When a fraction equals zero :

4.1 When a fraction equals zero ...
Where a fraction equals zero, its numerator, the part which is above the fraction line, must equal zero.

Now,to get rid of the denominator, Tiger multiplys both sides of the equation by the denominator.

Here's how:

3z-25
————— • 3 = 0 • 3
3
Now, on the left hand side, the 3 cancels out the denominator, while, on the right hand side, zero times anything is still zero.

The equation now takes the shape :
3z-25 = 0

Solving a Single Variable Equation :

4.2 Solve : 3z-25 = 0

Add 25 to both sides of the equation :
3z = 25
Divide both sides of the equation by 3:
z = 25/3 = 8.333
One solution was found :

z = 25/3 = 8.333