Simultaneous equations: 1) 3x + 2y = 23
2x - y = 6

2) 3x - 3y = 9
2x + y = 12

3) 4x + 2y = 34
3x + y = 21

(if you could answer with workings out that would be great)​

Twenty-five percent of the customers entering a grocery store between 5 p.m. and 7 p.m. use an express checkout. consider five randomly selected customers, and let x denote the number among the five who use the express checkout.

Planning for the possibility that your home might get struck by lighting and catch on fire is part of a plan

Yoku is putting on sunscreen. he uses 2\text{ ml}2 ml to cover 50\text{ cm}^250 cm 2 of his skin. he wants to know how many milliliters of sunscreen (c)(c) he needs to cover 325\text{ cm}^2325 cm 2 of his skin. how many milliliters of sunscreen does yoku need to cover 325 \text{ cm}^2325 cm 2 of his skin?