The next step in the equation is the quotient
I’m pretty sure it’s because you got the price wrong
Answer:
60.8 mm^2
D
Step-by-step explanation:
Remark
You have to assume that the left and right sides are both 9.3. The question is undoable without that assumption.
Next, you have to assume that The top is 7.8 mm across and both ends meet 9.3 at right angles. Again if that is not true, the problem can't be done. Sometimes people making these questions make errors which you are asked to correct.
Solution
So let's assume that everything I've assumed is correct.
Find the area of the rectangle.
Area = L*W
L = 9.3
W = 7.8
Area = 7.8 * 9.3
Area = 72.54 Do your rounding at the end.
Now find the are of the triangle that has been cut out.
The height = 3
The base = 7.8
Area = 1/2 b * h
Area = 1/2 7.8 * 3
Area = 11.7
The area of the figure = area of the rectangle - the triangle's area
Figure Area = 72.54 - 11.7
Figure Area = 60.84
You did ask for the EXACT value, which no one has posted yet. The exact value is √(2 + √3)/2. To three decimal places, that is .966.
As for how I got that, I started with a 30-60-90 triangle and extended the longer side by the length of the hypotenuse to get a 15-75-90 triangle, then used Pythagoragus. For some reason, though, most students have an easier time using a half-angle formula, so feel free to do it that way.
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OK, sorry, I see Awesome Sauce also gives an exact value. It is also correct, just looks a little different.
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From your comment in Additional Details, it appears you want to use the angle difference relation: cos(π/12) = cos(π/4 - π/6). That works also, but you need to get the formula right, which is:
cos(a - b) = cos a * cos b + sin a * sin b
For cos (45 - 30), this gives cos 45 * cos 30 + sin 45 * sin 30 = √2/2 * √3/2 + √2/2 * 1/2 = √2/4(√3 + 1). This is yet another expression for the same exact value.
Lets assign some variables: Let
y = Darren + Michael
x = Brian.
Given:
y = 2x + 30 (Darren and Michael [y] earn [=] 30 more than[+30] twice what Brian earns[2x])
y = 3800 (Darren and Michael [y] earn [=] $3800)
Solve for x: What Brian earns.
I will solve this by substitution. Plugging in 3800 for y:
3800 = 2x + 30 subtract 30 from both sides
3770 = 2x divide by 2 on both sides
1885 = x flip the equation
x = 1885
Brian earns $1885 per month.