Answer:
Not true
Step-by-step explanation:
x + (2x + 5) = 3(x – 4)+7
Opening bracket on left and side and distributing 3 over (x-4) on right hand side
x+2x+5=3x-3 x 4 + 7
adding like terms
3x+5=3x-12+7
3x+5=3x-5
Hence
5 = -5
Which is not possible , Hence the equation given to us is false.
When you add and subtract be sure that the two fractions have the same denomination, and then add/subtract the numerators. I always do cross multiplication of the two fractions to obtain the same denominators-although there are various ways to do this.
Multiplying fractions is simply straight across.
Dividing fractions:
Keep, change, flip.
Keep the first fraction the same, change the sign to its opposite (ex:division flips to multiplication), and flip the numerator and the denominator of the second fraction. Then, preform the arithmetic from your "new" problem.
Answer:
cos(x) -csc(x)
Step-by-step explanation:
It is helpful to know the relations between the trig functions:

__
Then the given expression can be simplified as follows:

The second one because of the points and it would need to be pc=13
(5x-7)2 + 140x
= 25x2 - 70x + 14 + 140x
= 25x2 + 70x + 14
= (5x+7)2