<h2>Solving Equations</h2>
To solve linear equations, we must perform inverse operations on both sides of the equal sign to <em>cancel values out</em>.
- If something is being added to x, subtract it from both sides.
- If something is being subtracted from x, add it on both sides.
- Same with multiplication and division. If x is being divided, multiply. If x is being multiplied, divide.
We perform inverse operations to<em> combine like terms</em>. This means to get x to one side and everything else on the other.
<h2>Solving the Questions</h2><h3>Question 1</h3>

Because 7 is being added to x, subtract it from both sides:

Because x is being multiplied by 5, divide both sides by 5:

Therefore.
.
<h3>Question 2</h3>

Here, we can group all the x values on the left side of the equation. Subtract 5x from both sides:

To isolate x, subtract 4 from both sides:

Divide both sides by 2:

Therefore,
.
15 because 3/4 is equivalent to 75% and 75% of 20 is 15.
The value of the product expression (-2x-9y²)(-4x-3) is 8x² + 6x + 27y² + 36xy²
<h3>How to evaluate the product?</h3>
The expression is given as:
(-2x-9y²)(-4x-3)
Expand the expression
8x² + 6x + 27y² + 36xy²
Hence, the value of the product expression (-2x-9y²)(-4x-3) is 8x² + 6x + 27y² + 36xy²
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Answer with Step-by-step explanation:
We are given that
A and B are matrix.
A.We know that for two square matrix A and B
Then, 
Therefore, it is true.
B. det A is the product of diagonal entries in A.
It is not true for all matrix.It is true for upper triangular matrix.
Hence, it is false.
C.

When is a factor of the characteristics polynomial of A then -5 is an eigenvalue of A not 5.
Hence, it is false.
D.An elementary row operation on A does not change the determinant.
It is true because when an elementary operation applied then the value of matrix A does not change.
Answer:
so i don't know if they are separate math problems but for the first question i got M=5 and the second question i got M=-7/2
Step-by-step explanation:
hope this helps please mark brainliest