Given:

He does mistake in the order of giving preference.
We should give preference in the order, division, multiplication, addition, subtraction.
But, he gave the first preferrence to the subtraction.
72-8=64
Next, he used division
64/2=32
Next he adds 32 with 8.
So, he gets 50.
But the actual simplification is,
Simplifying we get,

Hence, the correct value of the expression is 86.
Answer:
4 or -625x^4 (Just in case I misunderstood)
Step-by-step explanation:
The degree is always the power of something. Since -5x has a power of 4, its degree is 4.
Just in case I misunderstood the question, I will solve it another way that I think you meant. (-5x)^4 is -5^4 times x^4.
-625 times x^4 is -625x^4.
Answer: ST is equal to 12
Step-by-step explanation:
If RU is equal to 24 as a whole and we are given that RS and TU are equal to 6 then we could set up an equation and solve for ST.
6 + 6 +x = 24 where x is the length of ST
12 + x = 24
-12 -12
x = 12
Answer:
The new volume is 20litres
Step-by-step explanation:
This problem bothers on the expansion of gases
According to Boyle's law
The volume of a given mass of gas at constant temperature is inversely proportional to the pressure
P∝1/v
Pv= constant
Given data
P1= 1.5atm
v1 = 10 litter
P2=0.75atm
v2=?
Applying P1v1= P2v2
v2= P1v1/P2
v2= 1.5*10/0.75
v2= 15/0.75
v2= 20litres
It’s c (plane) if your asking for two-dimensional set of points