Okay, so for number 45, we are simplifying this expression. We are going to use “PEMDAS”, which is the Order of Operations. Parentheses, Exponents, Multiplication, Division, Addition, Subtraction. We do have a variable and a constant in parentheses, but we don’t know the “x” value, so we can’t subtract them. However, we can do The distributive property, which would mean mulling that 2 outside of the parentheses with everything in the parentheses. So that would make our expression look like this:
2x-4+5x
What we do now is combine like terms, which means all of the xs will go together, and so will the constants (but we only have one, so we’re not going to do that). Now we’ll add 2x and 5x, which equals 7x. Now that -4 will stay the same.
<em>Final Answer: 7x-4</em>
For number 46, it’s a little different. We don’t have any parentheses, but we do have decimals. We’re just going to combine like terms again, meaning we’ll add the .4b and the 1.2b, making our new expression (and final answer!) look like this:
<em>Final Answer: 1.6b -3.2</em>
Finally, number 47 is making us use fractions...(how dare you number 47!) It’s okay though, we’ll solve it. Now, depending on your teacher, we can do different things with this expression. If your teacher doesn’t like mixed numbers, we’ll do an improper fraction. If your teacher doesn’t like either of those, we’ll do decimals. But for now, I think we can use fractions then later convert them into mixed fractions or decimals. We have to combine the gs, and 6=28/4. So that would be 1/4 g+ 28/4 g, which would be 29/4 g.
<em>Final Answer: 29/4 g -2/3</em>
<em> </em><em> Or</em>
<em>Final Answer: 7.5 g -2/3</em>
<em>Or</em>
<em>Final Answer: 7 1/4 g -2/3</em>
48. Basically, the temperature, (-12), dropped by 14 degrees. When it DROPS, that’s a key word tha we have to SUBTRACT. (The temperature got lower by 14 degrees) So, we have to do -12-14. Because we’re doing “-14” we’re getting more negative. So, our final answer is...
<em>-26 Degrees Celsius </em>
or 