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Answer:
Step-by-step explanation:
The conjugate is found by changing the sign of the square root term.‡ (For this purpose, i = √-1.)
a) the sign of 3i is changed: 2 + 3i
b) the sign of sqrt(-5) is changed: 8 -sqrt(-5) = 8 -i√5
c) the sign of 2i is changed: 7 +2i
d) the sign of sqrt(7) is changed: 4 +√7
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‡ Actually, the conjugate of a binomial is formed by changing the sign <em>between</em> terms. The purpose is to allow the product of the binomial and its conjugate to be the difference of squares.
Conventionally, the conjugate of a complex number is the value with the sign of the imaginary part reversed. That is why (-2i+7)* = 7+2i.
15/10 = 18-x/x is the ratio of the larger to the smaller triangle
Cross multiply:
15x = 10(18 - x)
15x = 180 - 10x
25x = 180
x = 7.2
Plug back in to check
15/10 = 1.5
18-7.2/7.2 = 10.8/7.2 = 1.5 :)
A - side of small map
a+6 - side of larger map
(a+6)² - area of larger map
(a+6)² = 121
(a+6)² = 11² |√(...)
a+6 = 11 |-6
a+6-6 = 11-6
<span>a = 5
</span>Answer A. <span>5 inches by 5 inches</span>
