Answer:
cos(45°) = (√2)/2
Step-by-step explanation:
The cosine of 45° is the x-coordinate of the point on the unit circle where the line y=x intersects it. That is, it is the positive solution to the equation ...
x^2 +x^2 = 1
x^2 = 1/2 = 2/4 . . . . . collect terms, divide by 2, express the fraction with a square denominator
x = √(2/4) . . . . . . take the square root
x = (√2)/2 . . . . . simplify
The cosine of 45° is (√2)/2.
You can simplify this expression with PEMDAS (parentheses, exponents, multiplication/division, addition/subtraction)
Start with the expressions in the parentheses:
4-7=-3
4+7=11
The expression now reads -2(-3)+5(11). Now, simplify the multiplication expressions:
-2*-3=6
5*11=55
The expression is 6+55 which is 61.
Hope this helps!!
The answer is A.
If a redundant conclusion is reached in basic algebra this states that the variable holds all possible real values.
If you algebraically solve Kendra's you do achieve the true statement 5 = 5 (leaving out D). And if you test any value of x for the equation it does hold true (getting rid of B).
Hopefully this makes sense.