Hãy giúp tôi bài này bằng tiếng việt

65% of students in your school participate in at least one after school activity. if there are 980 students in you school, how many do not participate in an after school activity?

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 value of m will create a system of parallel lines with no solution? y = mx - 6 8x - 4y = 12