I find that your reaction is not at all uncommon. Many people I've encountered, both in real life, and online, have what I like to call "math anxiety," where their brain just freezes up and they get stupefied by a math problem, even an easy one. However, my strategy has always been to remove the math, as best I can. Because, in my experience, it's not the calculations that give people grief, it's the fact that it's math.
You say you've done the first step of squaring the 3/5 to get 9/25. That's great. A good start. So now you have:
\(\displaystyle -\frac{1}{2}\cdot \frac{9}{25}-1\)
According to PEMDAS, the step after Exponents is Multiplication/Division. So, we want to multiply through the fractions. Ignoring the minus sign for the moment (since all it does is change the sign of the answer), we have:
\(\displaystyle \frac{1}{2}\cdot \frac{9}{25}\)
The multiplication can be thought in this way. You have a pizza. You cut it into 25 equal-sized pieces. Let's say your friends ate some of the pizza. So now, of those 25 pieces, you have only 9 left. That's the 9/25 term. What you want to do is eat half (1/2) of what's left and refrigerate the rest. How many slices would you have left in the fridge? Well, it's 9 divided by 2, or 4.5. But we don't like decimals in our fractions, so you need to change that fraction so the numerator and denominator are both whole numbers. What happens if we multiply both the numerator and denominator by 2? We'd get 4.5 * 2 / 25 *2 or 9/50. And finally, the minus sign has to be brought back in so the partial answer is -9/50. If you're uncomfortable with the concept of having negative slices of pizza, I don't blame you. Unfortunately, I can do little to help you cope with negative numbers. The best advice I can offer is practice, practice, practice. You will, over time, become more comfortable with them.
But in any case, the final step of the PEMDAS is Addition/Subtraction. This is not too difficult, if you remember a trick I'll show in a moment.
\(\displaystyle -\frac{9}{50}-1\)
So, we have our negative fraction of the pizza, and we need to subtract another whole pizza from it. You can always represent one as any fraction where the numerator and denominator are equal. Because whether it's 3 out of 3 slices, or 50 out of 50 slices, or 10000 out of 10000 slices, you still have one whole pizza. In this case, we'll pick 50/50 as our fraction for one.
\(\displaystyle -\frac{9}{50}-\frac{50}{50}\)
Because the denominators of the fractions are equal, we can treat temporarily remove the denominators and just subtract the numerators, then tack the denominator back on at the end. That becomes -9 minus 50, which is -59. Re-add the denominator and you get the final answer of -59/50. If your teacher prefers answers in decimal form, that's fine too...
\(\displaystyle -\frac{59}{50}=1.18\)
I know this was kind of a long post, but I hope it was also informative. If I lost you at any point, please feel free to ask. Either me or someone else here will help you.
