Describe and correct the error in solving for one of the variables in the linear system 4 x + 2 y equals 6 + 3 x + y equals 9

12

step-by-step explanation:

a triangle's   full angle is 180 degrees so 180 - 156 = 24. 24/2=12

1. which statement below is true for hyperbolic geometry?

answer: d  

the sum of the measures of the angles in a triangle is always less than 180 degrees.

2. identify the statement that is true in spherical geometry.

answer: d  

the sum of the measures of the angles of a triangle is greater than 180.

3. what can be said about the vertices of an equilateral triangle drawn in poincaré’s system?

answer: b  

the vertices are equidistant from the center of the circle.

4. satellites sputnik, yeltsin, and plekov often temporarily line up in order in a great circle. the circumference of the earth is 24,900 miles, and the satellites orbit at about 150 miles above the surface. if, while in a great circle, sputnik is 9,000 miles from yeltsin, and yeltsin is 10,500 miles from plekov, how far apart are sputnik and plekov?

answer: b  

6,342 miles

5. identify the statement that is true in spherical geometry.

answer: d  

two distinct lines intersect in two points.

during a construction project, engineers used explosives to excavate 140 feet of tunnel into a mountain. but because of time constraints and environmental concerns, they brought in a tunnel boring machine (tbm) to excavate the rest of the tunnel. the data table lists some observations an engineer made about the length of the tunnel after the tbm was introduced.

which equation represents the length of the completed tunnel based on the number of days since tbm was introduced?

the answer is y = 45x + 140