Let the root of X be the smallest A. - 4 b.4 c.0 D. does not exist I think we should choose D. x is a number ≤ 4. There are many columns of numbers smaller than 4~ I don't know if I'm wrong or the answer is wrong

Let the root of X be the smallest A. - 4 b.4 c.0 D. does not exist I think we should choose D. x is a number ≤ 4. There are many columns of numbers smaller than 4~ I don't know if I'm wrong or the answer is wrong

The answer is B, which means to find the minimum value of √ 4-x. of course, the minimum value of √ 4-x is 0, that is, x = 4

A and B climb a mountain. A climbs 10 meters per minute and starts for 30 minutes. B climbs 15 meters per minute. They both climb the mountain at the same time? How high is the mountain?

Suppose a takes X minutes to climb to the top of the mountain, then B takes (X-30) minutes to climb to the top of the mountain. From the meaning of the question, 10x = 15 (X-30), the solution is: x = 90, that is, a climbs in 90 minutes, then 10 × 90 = 900 meters. A: a climbs in 90 minutes, and the mountain is 900 meters high

1. Given that y = 0.5 is the solution of equation 6 (2Y + m) = 3M + 2, find the solution of equation MX + 2 = m (1-2y) about y
2. The purchase price of a commodity is 300 yuan, and the price is 450 yuan, but the profit is still 20% after the price reduction. How much discount is the commodity sold?
3. There are 100 apples in four plates. If you add 4 to the number of apples in the first plate, subtract 4 from the second plate, multiply 4 by the third plate, and divide 4 by the fourth plate, the numbers are the same. How many are the original numbers?

1: Let y = 0.5 be the solution of the equation 6 (2Y + m) = 3M + 2, 6 (2 * 0.5 + m) = 3M + 2, M = - 4 / 3 find the solution of the equation MX + 2 = m (1-2y) - 4x + 6 = - 4 (1-2y), 8y = - 4x + 10, y = - 0.5x + 1.25, x = - 2.52:450x-300 = 300 * 20%, x = 360 / 400 = 0.9 = 90% 3