Someone help me with my algebra homework please

15

General Formulas and Concepts:

Pre-Algebra

Order of Operations: BPEMDAS

Brackets Parenthesis Exponents Multiplication Division Addition Subtraction Left to Right  

Equality Properties

Multiplication Property of Equality Division Property of Equality Addition Property of Equality Subtraction Property of Equality

Step-by-step explanation:

Step 1: Define

Identify

5a - 10b = 45

b = 3

Step 2: Solve for a

Substitute in b [Equation]:                                                                                5a - 10(3) = 45Multiply:                                                                                                             5a - 30 = 45[Addition Property of Equality] Add 30 on both sides:                                  5a = 75[Division Property of Equality] Divide 5 on both sides:                                  a = 15

I'm pretty sure it's b). i try drawing the functions out and b is the one that stands out or isnt a "line"

1. 0.3 •4 is the same as 4 groups of 0.32. 7•0.8 is the same as 7 groups of 0.83. it increases by 0.5 every time, so 0.5x4 it increases by 0.9 every time, so 0.9x5. 0.9•12=10.86. 0.47•5=2.35i can finish the next ones in a separate post