The sum of twice a number and 15 is 9

Mathematics

2 answers:

34kurt3 years ago

4 0

$\huge \purple{\tt{Answer:}}$

Let the unknown number be x .

$\Large{\underline{\sf{According~to~question}}}$

$\sf {2x+15=9} \\\\\ \implies \sf{2x=9-15} \\\\\ \implies \sf {2x=-6}$

$\implies {\sf {x ={ \dfrac{ - 6}{2}}}} \\\\\ \implies \sf{x=-3}$

Illusion [34]3 years ago

3 0

Key word: sum

twice a number = 2n

Sum of that and 15 = 2n + 15

is = equals

Answer: 2n + 15 = 9

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See explanation.

Step-by-step explanation:

Let BC be the diameter of the circle with center at point O, AB be the chord and ∠ABC=30°. OD is the distance from the center to the chord.

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