Answer:
1;infroei[q
Step-by-step explanation:
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25q + 10d = 425
q + d = 20
First thing's first, picture 4 quarters. Do you know how much these 4 quarters are worth? Obviously, you'd answer one dollar, but take the time to think about how exactly you came up with this answer.
"Well, it's simple," you might think, "Multiply 0.25 by 4."
Similar to this train of thought, the first equation is formulated by doing exactly that. 'q' represents an unknown number of quarters, and 'd' an unknown number of dimes. We use 25q and 10d, because, well, we're multiplying their value by the number of coins. They're equivalent to 425 because the 20 unknown coins make $4.25 (I converted it to cents to get rid of the pesky decimals, but if you want to keep it as dollars that works too).
Because the equation states that there are 20 coins in total, we know that we can make the equation 'q + d = 20' since there are 20 quarters and dimes in total.
Let me know if you need any further explanation :)
-T.B.
H'(x) = 2f'(x)
h'(1) = 2*f'(1) = 2*4
h'(1) = 8
Question is Incomplete, Complete question is given below.
Prove that a triangle with the sides (a − 1) cm, 2√a cm and (a + 1) cm is a right angled triangle.
Answer:
∆ABC is right angled triangle with right angle at B.
Step-by-step explanation:
Given : Triangle having sides (a - 1) cm, 2√a and (a + 1) cm.
We need to prove that triangle is the right angled triangle.
Let the triangle be denoted by Δ ABC with side as;
AB = (a - 1) cm
BC = (2√ a) cm
CA = (a + 1) cm
Hence,
Now We know that

So;


Now;

Also;

Now We know that




[By Pythagoras theorem]

Hence, 
Now In right angled triangle the sum of square of two sides of triangle is equal to square of the third side.
This proves that ∆ABC is right angled triangle with right angle at B.
Answer:
She pays $566.10
Step-by-step explanation:
The mattress store marks a mattress up 100%. 100% of $225 is 225. We add 225 to 225 and get 510. Therefore, the store sells the mattress for $510 without tax. When Cassie buys the mattress, we have to add 11% tax. We change 11% to 0.11 and multiply that by the selling price (510). We get 56.10, so that is the tax. We add the tax to the selling price and get $566.10. Cassie pays $566.10 for the mattress.
I hope this helped and please mark me as brainliest!