I tried to include some explanations as well. Hopefully this helps.
Answer:
g=7.5
Step-by-step explanation:
2/3g=45
divide both sides by 2/3
g=7.5
or
g=7 1/2
Answer:

Step-by-step explanation:
Given

Required
Determine 

Open bracket

Equate the equation to 0

Express 3 as 1 + 1 + 1

Collect like terms

Group each terms

Factorize (starting with the first bracket)












Express 0 as 0 + 0 + 0

By comparison



Solving for 
Take square root of both sides

Add 1 to both sides


Solving for 
Take square root of both sides

Subtract 1 from both sides


Solving for 
Take square root of both sides

Subtract 1 from both sides


Substitute the values of a, b and c in 



9514 1404 393
Answer:
-11
Step-by-step explanation:
DeYanna's cards are ...
black: 2, 4, for a total value of 2+4 = 6
red: 7, 10, for a total value of -(7+10) = -17
Then the total value of DeYanna's cards is ...
6-17 = -11
Answer:
no.
Step-by-step explanation:
The sum of two side lengths have to be <u><em>greater</em></u> than the value of the remaining side length.
Hope this helps. Have a nice day you amazing bean child.