X + y = 40.....multiply by -4
4x + 6y = 180
-------------------
-4x - 4y = -160 (result of multiplying by -4)
4x + 6y = 180
------------------add
2y = 20
y = 20/2
y = 10 <===
x = 30
Answer:
5/2-7/2 i or 2.5-3.5i
Step-by-step explanation:
expand the fraction remove the parenthesis and then calculate
Answer:
square root of 65
Step-by-step explanation:
all i am going to say is, Pythagorean theorem.
Answer: 
Step-by-step explanation:
Given
It takes 20 min and 30 min for a person and his friend to paint a wall individually i.e.
In 1 min they cover
part and
part of wall respectively.
If the work together, 1 minute work is

Time required will be reciprocal of it
