Question

M²-n²=21. m-n=3. m×n=?

Answer 1

Объяснение:

поставвь 5звезд пж, удачи

Answer 2

Let's solve this system of equations step by step:

Given:

1. $M^2 - N^2 = 21$
2. $M - N = 3$

First, we can factor the left-hand side of the first equation using the difference of squares formula: $a^2 - b^2 = (a + b)(a - b)$. In this case, let $a = M$ and $b = N$. So, we have:

$M^2 - N^2 = (M + N)(M - N)$

Now, we can substitute the value of $M - N$ from the second equation into the factorization:

$21 = (M + N)(3)$

Divide both sides of the equation by 3:

$(M + N) = 7$

Now, we have a system of two equations:

1. $M + N = 7$
2. $M - N = 3$

Adding these two equations together eliminates the variable $N$:

$(M + N) + (M - N) = 7 + 3$ $2M = 10$

Divide both sides by 2:

$M = 5$

Now that we know $M$, we can substitute it back into the second equation to find $N$:

$5 - N = 3$

Subtract 3 from both sides:

$-N = -2$

Multiply both sides by -1:

$N = 2$

Now that we have the values of $M$ and $N$, we can calculate $M \times N$:

$M \times N = 5 \times 2 = 10$

Therefore, $M \times N$ is equal to 10.