7th grade happy winter vacation answers, happy summer vacation 7th grade math summer vacation homewo

One

1、b 2、b
5、(1)x-6>2 (2)a+b≥0

II

1, x 3 2, x> 3, x x<-4 5, c 6, c 7, (1) x>6 The number axis is omitted, and (2) the number axis is >-2 is omitted.

8. (1) x>2 number line means slightly (2) x> number line means slightly x<3 number line means slightly 10, x>3 11

III

Operation**(1) When x=2, y=15, when x=-2, y=3 (2)-17 8 x< (3) x -17 8 1, x 1 2 2, (1) 4000 yuan (2) 5 types: A 6, B 9; A7B8; A8B7; A9, B, Sun Shenxiang, 8; A10B5 (3)A=300, A6B9 is more advantageous.

Fourth

1、x
/18>x
.5km Operation**(1)C>A>B (2)R>S>P>Q Innovation Stage.

When m > n, do not agree; When m=n, it doesn't matter; When m

Five

1, b 2, d 3, (1) a + ab (2) x + y (3) 1 (4) ac 4, (1) 36a4 4b (note: 4 4 is the 4th power of 4, will not be explained later) (2) x (x-9).

5. (1) 5x-10y 2x-40 (2) x-20 130x+24 6, (1) 1 3x=4y 12xy, 5 12xy=5x 12xy (2) y x(x-y)=y-xy x(y-x) x (y-x) x (y-x)=x x(y-x) innovation stage -7, -7

Six

3, x 4-6 dac 7, (1) 2 xz (2) 10 3a(a+2) operation** omitted.

Seven

1, (1) x=0 (3) x=0 (Q2 4, (1) 2) Incorrect The denominator should be retained (3)-2x-6 (x+1)(x-1) Innovation stage Original formula = x+4 then beat (-root number 3) = (root number 3), correct.

Eight

1. M > blind Zheng Yuan perception and experience.

Nine

1. y=50 x 2, omitted 3, >2 3 4, m>1 2 5, d 6, b 7, (1) y=-18 x (2)x=-6 innovation stage omitted.

X

1-3 aad 4、(1)s=100000/d (2)200m (3)

XI

1, 2, 4, 2, C, 3, 10m long, 6m wide, innovation booth (1) 30min (2) invalid.

I don't know what year it is, and I dare to stick to roll the points.

、( Late with rain, wild ferry unmanned boat self-traverse.

Someone plagiarizes purely for the convenience of children...