Match the correct word to the correct definition. question 1 options: ptolemaic geocentric heliocentric scientific revolution cartesian coordinate system 1. a mathematical system created by this man; idea of locating a point where two lines come together 2. ptolemy’s theory that the earth is the center of the universe 3. idea or understanding of the universe created by ptolemy 4. copernicus’ idea that the sun is the center of the universe 5. a period of time beginning during the 1600s in which scholars made great progress in understanding the workings of nature. built upon the ideas of experimentation and observation.

Ptolemaic

3. Idea or understanding of the universe created by Ptolemy.

Claudius Ptolemy was a Greek mathematician and astronomer that created the Ptolemaic System, where the Earth is the center of the universe, this theory lasted until the Heliocentric theory came in place. According to Ptolemy's concept of gravity all matter fell down to the center of the universe, the Earth, and the divine bodies, such as the moon, the sun and the stars remained in place because they were attached to crystalline spheres.

Geocentric

2. Ptolemy's theory that the Earth is the center of the universe.

The Geocentric system viewed the Earth as the center of the universe in the solar system's structure. Ptolemy's Geocentric theory was the most accepted one and lasted until the 16th century with the Heliocentric theory. The Geocentric theory was based on the observation from the Earth, where the sun appears to revolve around the planet once a day, as well as the moon and the stars.

Heliocentric

4. Copernicus' idea that the sun is the center of the universe.

The Heliocentric theory was first proposed by Aristarchus of Samos, but since he couldn't explain why the stars appear at the same position if the Earth is moving, the Ptolemy's Geocentric theory was the one accepted at that time.

Therefor, the Heliocentric theory was officially accepted in the sixteenth century when Nicholas Copernicus proposed a mathematical model of the solar system, where the planets revolve around the sun, his astronomic model solved the previous mathematical problems and inconsistencies.

Scientific Revolution

5. A period of time beginning during the 1600s in which scholars made great progress in understanding the workings of nature. Built upon the ideas of experimentation and observation.

The Scientific Revolution set the ground for mathematics, astronomy, physics, chemistry and biology, it was a time where people began to question nature, and developed the Scientific method (observation, hypothesis, experimentation, conclusion) to explain those questions.

Cartesian Coordinate System

1. A Mathematical system created by this man; idea of locating a point where two lines come together.

René Descartes was a French mathematician who developed this system in 1637, the name Cartesian System is taken after him. Descartes developed the idea of locating a point in two intersecting axes; in this system points can be located measuring both horizontal and vertical distance from the origin (which is where the two axes intersect).

the right answer is d

8 - (2a + 7) = a + 40     distribute/multiply - into (2a + 7)

8 - 2a - 7 = a + 40

1 - 2a = a + 40       add 2a on both sides

1 = 3a + 40         subtract 40 on both sides

-39 = 3a       divide 3 on both sides

-13 = a

[proof]

8 - (2a + 7) = a + 40

8 - (2(-13) + 7) = -13 + 40

8 - (-26 + 7) = 27

8 - (-19) = 27

8 + 19 = 27

27 = 27