Answer:
The first is true.
8 · 21 = 168
The second is false.
The third is false.
The fourth is true.
Step-by-step explanation:
Answer:
28, 29, 30
Step-by-step explanation:
Answer:
D
Step-by-step explanation:
A. Sin 42=0.669
Cos=52=0.617
B. Sin 90=1
cos 90=0
C. cos30=0.866
sin 70=0.940
D. sin80=0.985
cos 10=0.985
Answer:
D
Step-by-step explanation:
So we have the equation:

And we want to solve for x.
We can solve it by completing the square.
First, subtract 58 from both sides:

Divide the b term by 2 and square it:

So, add 9 to both sides:

On the left, the perfect square trinomial pattern. Add on the right. So:

Take the square root of both sides:

The square root of -49 is 7i:

Add 3 to both sides:

So, our answer is D.
And we're done!
Answer: The cost of one sandwich is $4.25 and the cost of one cup of coffee is $2.25.
Step-by-step explanation:
Let x be the cost of one sandwich and y be the cost of one cup of coffee.
By considering the given situation, we have the following equations :-

Multiply 2 on both sides of equation (2) , we get

Subtract equation (1) from equation (3), we get

Put value of y in (1), we get

Hence, the cost of one sandwich is $4.25 and the cost of one cup of coffee is $2.25.