Answer:
4(30 +7) = 120 +28 = 148
Step-by-step explanation:
When applying the distributive property to integers, we usually break them apart according to place value. That is not the only way it can be done.
4×37 = 4(30 +7) = 4·30 +4·7 = 120 +28 = 148
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You can also break apart 37 other ways:
4×37 = 4(35 +2) = 4·35 +4·2 = 140 +8 = 148
4×37 = 4(40 -3) = 4·40 -4·3 = 160 -12 = 148
Or, you can break apart 4:
37×4 = 37(2 +2) = 37·2 +37·2 = 74 +74 = 148
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The distributive property is usually written in generic form as ...
a(b+c) = ab +ac
Then you may want to stop after the first couple of steps:
4(30 +7) = 4·30 +4·7
We can't tell if you're suppose to evaluate the expression or not. Check your reference materials for an example of this kind of problem.
A positive one because the nagatives cancel out
This revolves around exact trig values - no easy way to say this, you just need to memorise them. They are there for sin cos and tan, but I will give you the main tan ones below - note this is RADIANS (always work in them when you can, everything is better):
tan0: 0
tanpi/6: 1/sqrt(3)
tanpi/4: 1
tanpi/3: sqrt(3)
tanpi/2: undefined
Now we just need to equate -2pi/3 to something we understand. 2pi/3 is 1/3 of the way round a circle, so -2pi/3 is 1/3 of the way round the circle going backwards (anticlockwise), so on a diagram we already know it's in the third quadrant of the circle (somewhere between pi and 3pi/2 rads).
We also know it is pi/3 away from pi, so we are looking at sqrt(3) or -sqrt(3) because of those exact values.
Now we just need to work out if it's positive or negative. You can look up a graph of tan and it'll show that the graph intercepts y at (0,0) and has a period of pi rads. Therefore between pi and 3pi/2 rads, the values of tan are positive. Therefore, this gives us our answer of sqrt(3).
