Please help I am stuck

Use addition and subtraction to simplify the following polynomials. a. add polynomials: (3 – 4x + 8x^2) + (–6 + 2x – 5x^2) step 1: rewrite the polynomials without the parentheses. step 2: write the polynomial in descending order and use parentheses around like terms. step 3: add the like terms identified in step 2 to simplify the polynomial. b. subtract polynomials: (3x – 5 – 7x^2) – (–2 + 6x^2 – 5x) step 1: rewrite the polynomials without the parentheses. remember to multiply each term in the second parentheses by –1. show your work. step 2: write the polynomial in descending order and use parentheses around like terms. step 3: add the like terms identified in step 2 to simplify the polynomial.

Girardo is using the model below to solve the equation . girardo uses the following steps: step 1 add 4 negative x-tiles to both sides step 2 add 1 negative unit tile to both sides step 3 the solution is which step could be adjusted so that gerardo's final step results in a positive x-value? in step 1, he should have added 4 positive x-tiles to both sides. in step 1, he should have added 3 negative x-tiles to both sides. in step 2, he should have added 4 negative unit tiles to both sides. in step 2, he should have added 1 positive unit tile to both sides.

Which shows a reasonable estimation for 124% of 42 using the distributive property?