The answer is <span>He subtracted 10 from the right side instead of adding 10 to the right side
Let's solve it:
</span><span>2x + y = 5
x − 2y = 10
________
Rearrange first equation to get y:
y = 5 - 2x
________
Substitute y into the second equation:
x - 2(5 - 2x) = 10
________
Multiply the terms:
x - 10 + 4x = 10
________
Combine the terms:
5x - 10 = 10
________
Add 10 on the both sides of the equation:
5x = 10 + 10
5x = 20
x = 4</span>
Step-by-step explanation:

Answer:
(ab - 6)(2ab + 5)
Step-by-step explanation:
Assuming you require the expression factorised.
2a²b² - 7ab - 30
Consider the factors of the product of the coefficient of the a²b² term and the constant term which sum to give the coefficient of the ab- term
product = 2 × - 30 = - 60 and sum = - 7
The factors are - 12 and + 5
Use these factors to split the ab- term
= 2a²b² - 12ab + 5ab - 30 ( factor the first/second and third/fourth terms )
= 2ab(ab - 6) + 5(ab - 6) ← factor out (ab - 6) from each term
= (ab - 6)(2ab + 5) ← in factored form
Given that the triangle is a right angled triangle, to solve for x we shall use the Pythagorean theorem given by:
c^2=a^2+b^2
where:
c is the hypotenuse
a and b are the legs.
c=10
a=6
b=(x-6)
thus plugging the values in the equation and solving for x we get:
10^2=6^2+(x-6)^2
100=36+x^2-12x+36
100=x^2-12x+72
0=x^2-12x-28
factoring the above we get:
0=(x+2)(x-14)
hence
x=-2 or x=14
given that there is no negative distance then
x=14
thus the value of x is 14
Answer:
It can never be a prime number.
Step-by-step explanation:
This is because the product of the two prime numbers are divisible by those two numbers, therefore going against the definition of a prime number. For example 3 and 5 are prime numbers and their product is 15. 15 can be divided by 3 and 5 so it is not a prime number.
Hope this helps.