Dgbcool Dgbcool

14-07-2017
Mathematics

contestada

Amy purchased 17 pencils and 18 pens for a fund-raiser at school and spent $61.50. Jocelyn purchased 10 pencils and 21 pens and spent $57. How much does each pencil cost?

Respuesta :

texaschic101 texaschic101

14-07-2017

x = pencils, y = pens

17x + 18y = 61.50....multiply by 21
10x + 21y = 57 ....multiply by -18
------------------------
357x + 378y = 1291.5 (result of multiplying by 21)
-180x - 378y = - 1026 (result of multiplying by -18)
-----------------------add
177x = 265.5
x = 265.5 / 177
x = 1.50 <== cost for a pencil
pens(y) cost 2.00

Answer Link

Otras preguntas

Many of Theodore Roosevelt's actions influenced the course of the United States, and indeed, the world. What do you like or not like about Roosevelt? Do you agr

The lines that travel from west to east and that are highlighted in yellow on this map are __________.

The Question is in the photo ^ is it True or False?

In a chemical reaction, the __________ is consumed completely during the reaction. A) stoichiometry B) excess reagent C) ideal compound D) limiting reactant

The Framers who wrote the Constitution originally stated that the President could serve ____

Practice and specific training can improve components of skill-related fitness limited by heredity. Please select the best answer from the choices provided. T F

Emma brandy and Damien will cut a rope that is 29.8 feet long into 3 jump ropes. Each of the three jump ropes will be the same length l. Write a division senten

Jordan notices that the bottom part of a cliff is worn away. Why is the cliff worn away the most near or under the level where the water is?

What is least likely to be considered a part of the context that a speaker must consider before giving a speech about climate change? A. The knowledge level of

which type if immunity provides lifetime protection for the body against a specific pathogen? A. active B.incomplete C.complete D.passive pleaseee help me :)