Mathematics Classic Examples Junior High School Level

Be concise and concise! I think basic training is more important.

Summary. Hello topic.

Hello topic. These questions.

OK Question 5 Select B

The sixth question is A120 degrees.

The A in question 6 is 30

Oh oh, that's c, it's 120 degrees.

Seventh c, 8th b

First give you a question, you see if it's okay, by the way, you are a candidate in that area, for example: the parabola and the straight line intersect at the point a(,1), find:

1) the coordinates of point A and the coordinates and axis of symmetry of parabolic vertex C;

2) Are there any other intersections between the parabola and the straight line? If so, request the coordinates of this intersection B, if not, please explain the reason.

And find the area of the triangle formed by the three points a, b, and c.

7(1)a(1,1) vertex c(0,0) axis of symmetry is the y-axis.

2) (3,9) The triangle has an area of 3

Doesn't that kind of school have school-based textbooks If not, it is recommended to buy "Growing with You".

Alas.. I'm in a parallel class. You still study carefully to buy a few useful books.

Set up to rise by x yuan.

10+x)(500-20x)=6000

Let's do the math for yourself, a quadratic equation, and the result is a positive number.

The screenshot is too small to see clearly.

Set up x yuan. 10+x)*(500-20x)=6000

x>0x=5, so it will increase by 5 yuan per kilogram.

First of all, it is important to know that Group A walks the same distance as Group B.

Car speed: walking speed = 30:4 = 15:2

Distance by car: walking distance = 15:2

See**: The orange line segment is the distance traveled by the car (omitting the part that was sent to Group B at the end) The green line segment in front is the distance walked by Group B, and the green line segment in the back is the distance traveled by Group A.

Know, orange line segment (car distance): green line segment (distance traveled by people) = 15:2 so: (15 + 2 + 2 2) 2 = 18 km distance = portion.

1 part of the distance: 18 and 25/35 (km).

So point A is 5/7 from Beishan: 1 and 5/7 2=3 and 3/7 (km) Hope it helps you, o( o thank you

If you have any questions, please ask me and I will try my best to answer them!

I'm in the sixth grade, and it's just a similar question that the teacher has done for us so I can answer it for you.

I don't know if my answer is correct, I can only ask you to check it, thank you for your cooperation!

The car goes back to pick them up and multiplies it by two

Set: point A is x km away from Beishan;

x/4=/30

x= km for solving the equation

1:x+y=200

105%x+115%y=225

5%x+15%y=25

5%x+5%y+5%y+5%y=25

5%(x+3y)=25

x+3y=500

2y=x+3y-(x+y)=500-200=300y=150 tons.

x = 200 - y = 50 tons.

2:x+y=290

x/60+y/100=

x+y)/100=

x/100+y/100=

x/60+y/100）-（x/100+y/100）=x/60-x/100=

100x/60-x=60

40x/60=60

40x=3600

x=90km

y=290-90=200km

3:am=x,an=9x/8

channel = y3x + 2y = 18

18x/8+y=13

3x+2y=18x/8+y+5

3x+y=18x/8+5

24x+8y=18x+40

6x+8y=40

6x+8y=3x+2y+(40-18)

6x+6y=3x+22

3x+6y=22

3x+6y=3x+2y+(22-18)

4y = 4y = 1 meter.

The head hurts around, so let's take the extra points quickly.