Answer:
She could have just done 42-23 = x and solved the equation in one step because if 23 and x add up to 42, then subtracting one from 42 will result in the other. This means both equations are equivalent, but 42-23 is faster and simpler.
The sum of the degrees for all triangles is 180, so just add the two you have and subtract from 180.
1. 58 + 47 = 105
180 - 105 = 75
Therefore x = 75
2. 91 + 26 = ?
180 - ? = ?
etc
Answer:
c, if wrong sorry
Step-by-step explanation:
Technology comes from the Greek root
, meaning art or craft.
For the Greeks, a straightedge and compass was technology.
The nice thing about a straightedge and compass construction of any length is that there's always a corresponding algebraic form consisting of natural numbers combined via addition, subtraction, multiplication, division and square rooting (of positive numbers). So we get an "exact" answer, at least using radicals.
Compare that to the typical calculating technology we use today where the square roots turn into approximations. The calculator is worse, turning an exact answer into an approximation.
Straightedge and compass constructions play a large role in the development of mathematics but they're not really better, it's just how things went. By restricting ourselves to straightedges (linear equations) and compasses (circles, quadratic equations) we restricted the possible lengths we could construct. Understanding exactly how propelled mathematics forward for a couple of thousand years.
First find the slope of the line that passes through (4,-1) and (-2,3) by calculating "change in y" / "change in x"
So slope = -4/6 = -2/3
Remember the format y = mx + b?
So pick any of the two coordinates (I'll use (4,-1)) and sub in what you can.
-1 = -2/3(4) + b
Solve for b and you'll get 1.66666.... aka 1 2/3
So the equation is y = -2/3x + 5/3
Now for the next question.
So 5/2.5 = y/10
cross multiply and simplify and you'll get y = 20