
via the angle sum formula of sin


which proves the second choice
the third choice is wrong since for x=0,y=0 it will show that 2=1 which is incorrect
for the fourth one you can do some thing similar to choice one just expand the sum formula of sin and that should be true too
so
the first , the second and the fourth are all true
Answer:
Juan has to work at least 21 weeks.
Step-by-step explanation:
Juan earns $3 a day, then he earns $21 per week.
Let x be the number of weeks Juan works. He will earn $21x in x weeks.
Juan has saved $213,
He earns $21x,
Juan's total earnings are $213+$21x.
He needs to save at least $654, so

Juan has to work at least 21 weeks.
<span>Volume of a square = (s)(s)(s) and s=5a+4b
Therefore: (5a+4b)(5a+4b)(5a+4b)=
(25a^2+40ab+16b^2)(5a+4b)=
(125a^3+200a^2b+80ab^2+100a^2b+160ab^2+64b^3)= (125a^3+300a^2b+240ab^2+64b^3)
You just multiple the first time the second and then do so again with the combination of the first two times the second. A little cleaning up and you are left with an equation in terms of a and b.</span>
Answer:
1. equation
2.equation
3.equation
4. expression
5.expression
6.equation
7.expression
8.equation
9.expression
anything with = is an equation, without is expression.
Answer:
It is all determined by how many spaces and which way the decimal point moves.
Step-by-step explanation:
So here are two examples
<em>Example 1:</em>
500000.00
To write this in scientific notation you would move the decimal place to the left.
You would move it 5 digits to the left so the exponent of 10 would be 5

<em>Example 2</em>
0.0000042
Here to write this in scientific notation you move the decimal place to the right.
You would move it 6 digits to the right so the exponent would be -6
