Help me solve two math problems and get extra points

x-y=m-5 is substituted by + to get x=2m-1 to get y=m+4

x+y=3m+3 Because the value of x is negative and the value of y is positive, 2m-1 is less than 0

m+4 is greater than 0 so -4

1.The addition of the two formulas gives 2x=4m-2 i.e. m=because x is a negative number, that is, the maximum cannot reach 0

Let's take 0 as the maximum x value and try m=

That is, m<

2.The two equations want to subtract 2y=2m+8, i.e., m=y-4, because y is a positive number, i.e., y is smaller and greater than 0.

Bring in 0 as the smallest y.

m=-4, so must m>-4

Together, it's -4>m>

If the value of x is negative and the value of y is positive, x-y is less than 0

M-5 is less than 0

m is less than 5

Add the two formulas x=2m-2<0

The two equations are subtracted y=m+4>0

Inequality group: -4

Because x is negative and y is positive, so x-y is negative, so m-5 is zero, so m 5Because + is 2x=4m-2, m1 2So m has a range of 1 2 m 5.

I'm in junior high school, and I've always taken the math test to 108 or above!

4 5 of A is equal to 3 4 of B

A equals B: 3 4 4 5 = 15 16

B: 310 (15 16+1) = 160

A: 310-160=150

4/5 of number A is equal to 3/4 of number B.

i.e. 4A, 5=3B, 4

i.e. A = 15 B 16

A + B = 15 B 16 + B = 31 B 16 = 310 B = 160

A = 150

Let A be x, then B is 310-x

x*4 5=(310-x)*3 4 solution x=150

So B = 310-150 = 160

27 + 9 = 36 36 3 = 12 12-8 = 427 * 3 = 81 81 9 = 9 9-8 = 18 to the third power to get 2 27 9 = 3 2 + 3 = 5 The second problem is solved with this program. . . There are so many solutions ...

#include

main()

int s,i,j,m,n,k,a[8],p=0,q;

for(i=5;i<=9;i++)

for(j=0;j<=9;j++)

if(j==i)continue;

for(k=0;k<=9;k++)

p=0;for(n=0;n<=4;n++)

if(a[n]==i||a[n]==j||a[n]==k||a[n]==m)

if(p==0)printf("%d",s/2);}

27/(9/3)-8=1

The remaining 2 answers used cube roots, which took 20 minutes for brain cells.

3rd cubic root of 27) +9-8=4

8-9 (3rd cubic root of 27) = 5

The programming can be solved very quickly, and it is not easy to calculate if it is calculated.

The first question doesn't seem to be clear?

The second question is like this:

fourfour

One by one. ei ght

Again: four

I tried a lot of numbers in the group, but I couldn't get it right.

What about e i ght?

The four-digit number is: 8532

The five-digit number is: 17064

2。If these 9 letters represent different numbers, then there is no answer, and the single digit does not match.

Question 1:

5's hasn't been counted yet.

Isn't there only one answer to the second question? If there is no restriction on letters, I'll report one:

Starting from 3, we get 3*3+1 = 10, and then we get 5, 16, 8, 4, 2, 1

Later, from 1 to 4, and then the cycle gives the sequence of 4, 2, 1.

It can be seen that 1, 2, and 4 can all be obtained, so C should be chosen

1 has 1, 2 has 2, 3 has 3...

So the last 1 is in the 1 term in the coincidental line, the last 2 is in the 1 + 2 = 3 term, and the last 3 is in the 1 + 2 + 3 = 6 terms.

The last n is in 1+2+3....n items. That is, n(n+1) 2 terms on Li Kuan.

Because 63*64 2=2016, 62*63 2=1953, 62*63 2 < 2011 < 63*64 2, item 2011 is 63

Thank you

op= (of+om) means that it is collinear, so the four-point line is a parallelogram, so that f1o=pm=c, and pm is perpendicular to the right alignment, so the eccentricity e=pm pf2=(2a+pf1) c=......

(1) The unit price of toffee: the unit price of fruit candy = 15:10 = 3:2 The weight of toffee and fruit candy:

18 (3 - 2) = 18 (kg).

The amount of money that mom brings:

18 (3+2)=90 (RMB).

A: My mother brought 90 yuan.

2) Assuming that for every more than a ton of water used in May, a water bill should be paid:

yuan) the excess is:

26-21) (t).

The part that is not exceeded is:

A: When the water does not exceed 5 tons, enjoy *** yuan per ton.

The water bill for June is:

5+ yuan).

A: The water fee in June is RMB.

Question 1: The unit price ratio of toffee to fruit candy = 15:10 = 3:2 The weight of toffee and fruit candy:

18 (3 - 2) = 18 (kg).

The amount of money that mom brings:

18 (3+2)=90 (RMB).

A: My mother brought 90 yuan.

2.Assuming that for every ton of water used in May, a water bill should be paid:

yuan) the excess is:

26-21) (t).

The part that is not exceeded is:

A: When the water does not exceed 5 tons, enjoy *** yuan per ton.

The water bill for June is:

5+ yuan).

A: The water fee in June is RMB.