Math P48 page 2, 3, 5, 8, 9 nine answers! ! There must be a process and a solution!

2. Let one of them be X and the other 1 be X+2 or X-2.

X*(X+2) or (X-2)= 168,

X 1 = - 14，。 X2 = 12, or X 1= 14, X2=- 12, so the two even numbers are-14 and -6554.

3. One of them is X and the other is14-X. According to the meaning of the question:

1/2*X*( 14-X)=24

X*X- 14*X+48=0，

X 1=6。 X2=8。 So the lengths of the two right angles are 6CM and 8CM respectively.

5. If the side length is x and the circumference is 4X, one diagonal line is a and the other is10-a. According to the meaning of the topic:

-(a*a- 10a)/2= 12

a*a- 10a+24=0

a 1=4，a2=6

Therefore, the lengths of the two pairs of lines are 4 and 6, respectively, so

X*X=4+9= 13

The arithmetic square root of x = 13. The arithmetic square root with a circumference of 4 * 13. = 14.4cm，