4X + 25 * 3 = 21.9

4X + 25 * 3 = 21.9

4x + 25×3 = 21.9
4x + 75 = 21.9
4x = 21.9 - 75
4x = - 53.1
x = - 531 / 40

It is known that the equation MX + NY = 10 has two solutions: x = - 1, y = 2 and x = - 2, y = - 1. Find the value of M and n

X = - 1, y = 2 into MX + NY = 10
2n-m=10
X = - 2, y = - 1 into MX + NY = 10
-2m-n=10
Then M = - 6
n=2

It is known that x = 1, y = 4 and x = - 4, y = - 6 are all solutions of the equation MX + NY = 10 about X and y

mx+ny=10
m+4n=10
4m+16n=40 (1)
-4m-6n=10 (2)
10n=50
n=5
m=-10

If the two solutions of the equation MX + NY = 6 are {x = 1, y = 1 {x = 2, y = - 1, then the square of M + the square of n=

The two solutions of MX + NY = 6 are {x = 1, y = 1 {x = 2, y = - 1
m+n=6
2m-n=6
Two equations are established
m=4,n=2
So:
Square of M + square of n = 20

Given that the equation MX + NY = 10 has two solutions, x = - 1, y = 2 and x = 2, y = - 1, then M = how much, n = how much?

Substituting its two solutions into the equation MX + NY = 10, we get the system of equations - M + 2n = 10, ① 2m-n = 10, ② we get the system of equations M = 10, n = 10

If the two solutions of the equation MX + NY = 6 are {x = 2, y = - 1 {x = 1, y = 2, then M = () n = ()

X = 2, y = - 1, x = 1, y = 2 are substituted into the equation respectively
2m-n=6 (1)
m+2n=6 (2)
(1)×2+(2)
5m=18
m=18/5
(2)×2-(1)
5n=6
n=6/5
m=18/5 n=6/5

If the two solutions of the equation MX + NY = 6 are x = 1y = 1, x = 2Y = − 1, then the value of M, n is ()
A. 4，2B. 2，4C. -4，-2D. -2，-4

Substituting x = 1y = 1, x = 2Y = − 1 into MX + NY = 6, we get m + n = 6, ① 2m − n = 6, ②, ① + ② get 3M = 12, that is, M = 4, substituting M = 4 into ① get n = 2, so we choose: a

If the solution of the equation MX + NY = 6 is: {x = 1, y = 1 and {x = 2, y = - 1, find the value of M n

m＝4 n＝2

It is known that the system of equations x = 1, y = 2 is the solution of the system of equations MX + NY = 3, NX my = 9?

m=-3 n=3 m+n=0

If M and N are opposite numbers in the system {x + my = 2 3x + NY = 0, then x =?

x+my=2 (1)
3x+ny=0 (2)
(1) Formula + (2) formula
We obtain 4x + (M + n) y = 2
If M and N are opposite to each other, then 4x = 2 and x = 1 / 2