I'm looking for two math problems in grade one! 1. Find all positive integer solutions of xy-3x-3y + 6 = 0 2. Judge the number of positive solutions of the equation x ^ 3-2x ^ 2 + 2 = 0 by classification discussion Please write down the process clearly!!!!!!!!!!

I'm looking for two math problems in grade one! 1. Find all positive integer solutions of xy-3x-3y + 6 = 0 2. Judge the number of positive solutions of the equation x ^ 3-2x ^ 2 + 2 = 0 by classification discussion Please write down the process clearly!!!!!!!!!!

x=6,y=4
x=4,y=6
When x > = 2, x ^ 2 (X-2) + 2 = 0, it is obvious that there is no solution in this interval
When 0

Xiao Li and Wang bought the same number of envelopes and the same amount of writing paper. Xiao Li wrote some letters with the paper he bought, one for each letter. Xiao Wang also wrote some letters with the paper he bought, three for each letter. As a result, Xiao Li used all the envelopes, but there were 50 left. Xiao Wang used all the paper, but there were 50 left How many letters and envelopes do people buy?

Let each of them buy y sheets of writing paper and X envelopes. From the meaning of the question, we get y − x = 50x − Y3 = 50, and the solution is x = 100y = 150. A: they each buy 150 sheets of writing paper and 100 envelopes

Given that the nonnegative real numbers x, y, Z satisfy x − 12 = 2 − Y3 = Z − 34, w = 3x + 4Y + 5Z. Find the maximum and minimum of W

Let x − 12 = 2 − Y3 = Z − 34 = k, then x = 2K + 1, y = - 3K + 2, z = 4K + 3, ∵ x, y, Z are nonnegative real numbers, ∵ 2K + 1 ≥ 0 − 3K + 2 ≥ 04k + 3 ≥ 0, the solution is - 12 ≤ K ≤ 23, then w = 3x + 4Y + 5Z = 3 (2k + 1) - 4 (3K-2) + 5 (4K + 3) = 14K + 26, ∵ - 12 × 14 + 26 ≤ 14K + 26 ≤ 23 × 14 + 26, that is 19 ≤ w ≤ 3513