Answer: Hello there!
here we have two equations:
1) x + 3y = 7
2) 2x + 4y = 8
a) first we want to isolate x in the first equation:
x + 3y = 7
x = 7 -3y
done!
b) now we want to replace it in the second equation, and in this way get a equation that depends only on the variable y.
2x + 4y = 8
2(7 - 3y) + 4y = 8
c) now we sole this equation and obtain the value of y.
14 - 6y + 4y = 8
14 - 2y = 8
-2y = 8 - 14 = -6
y = 6/2 = 3
d) now we have the value of y, and we can substitute it on the equation that we got in the part a)
x = 7 - 3y
x = 7 - 3*3 = 7 - 9 = -2
e) now we knowt that x = -2 and y = 3, then the pair (x,y) can be written as:
(-2,3).
Step-by-step answer:
Referring to the attached diagram, the resultant of two forces each with magnitude F and inclined to each other at 2a equals
Ra = 2Fcos(a) ..............................(1)
Similarly, the resultant of two forces each with magnitude F and inclined to each other at 2b equals
Rb = 2Fcos(b)..............................(2)
We are given that
Ra = 2Rb ....................................(3)
Substitute (1) & (2) in (3) gives
2Fcos(a) = 2(2Fcos(b))
Expand
2Fcos(a) = 4Fcos(b)
Simplify
cos(a) = 2 cos(b) QED
Note: Please note that you might have a faster response if you posted this question in the physics or the (new) Engineering section.
Have a nice day!
An expression given is to subtract a – b – c from the sum of 3a – 2b + 4c and 3b – 2c .
<h3>What is the
expression about?</h3>
An expression in math is known to be the putting together of numbers, variables, etc.
For the expression above,
(3a - 2b + 4c) + (3b - 2c) - (a - b - c)
Therefore:
= 3a - 2b + 4c + 3b - 2c - a + b + c
The answer will be = 2a + 2b + 3c
Learn more about expression from
brainly.com/question/723406
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Answer:
I wish I could hep but idk
Step-by-step explanation:
Answer:
Step-by-step explanation: hope this help :)