Question

21x+3y=36 если x=4 y=25x-3y > 12 если x=5 y=2​

Answer 1

1)
$21x + 3y = 36$
$21 \times 4 + 3 \times 2 = 36$
$90 > 36$
2)
$5x - 3y > 12$
$5 \times 5 - 3 \times 2 > 12$
$25 - 6 > 12$
$19 > 12$

Answer 2

Let's solve the equations step by step using the provided values for x and y.

1. 21x + 3y = 36 (Given equation)

Given x = 4 and y = 25x - 3y: x = 4 y = 25(4) - 3y

Now, substitute the value of y in terms of x into the first equation:

21x + 3(25x - 3y) = 36

2. Solve for x:

21x + 75x - 9y = 36 96x - 9y = 36

3. Given x = 5 and y = 2:

Now substitute the values of x and y:

96(5) - 9(2) = 480 - 18 = 462

So, the equation 21x + 3y = 36 is satisfied when x = 4 and y = 462.

4. Check the second condition:

Given x = 5 and y = 2:

25x - 3y > 12 25(5) - 3(2) > 12 125 - 6 > 12 119 > 12

The inequality 25x - 3y > 12 is true when x = 5 and y = 2.

To summarize:

1. For the equation 21x + 3y = 36, it is satisfied when x = 4 and y = 462.
2. For the inequality 25x - 3y > 12, it is true when x = 5 and y = 2.