How to factor
49y^{2}-9x^{2}

(7y + 3x)(7y - 3x)

Step-by-step explanation:

a² - b² = (a + b)(a - b)

49y² - 9x² = (7y)² - (3x)²                   {a = 7y ; b - 3x}

               = (7y + 3x)(7y - 3x)

two data sets with the same median will not have the same varaibility

step-by-step explanation:

the inequality is:

250c+180g≥950

step-by-step explanation:

let c denotes the number of days in a week   miyoko worked as a cryptographer.

and g denotes the number of days in a week she works as a geologist.

now we are given that she earns $250 for every day she works as a cryptographer,and earns $180 for every day she works as a geologist.

now miyoko's goal is to earn more than $950 this week.

hence, the inequality could be represented as:

250c+180g≥950