Determine whether the graphs of the two equations are perpendicular x-7y=4 and 21x+3y=11

Mathematics

1 answer:

Sveta_85 [38]3 years ago

3 0

Step-by-step explanation:

when multiplied together, the gradients of the 2 graphs should equal -1 (of they are perpendicular).

x-7y=4

-7y= -x + 4

y= -1/7 x + 4/7

21x+ 3y=11

3y=-21x+11

y=-21/3 x + 11/3

-21/3 * -1/7 = 1

when multipled together, the 2 gradients dont equal -1 therefore they are not perpendicular

unless I've made a mistake with the signs at some point haha

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Each step in a procedure to solve this equation is shown. Equation: 5x – 7 = 3(x + 1) Step 1: 51 – 7 = 3x + 3 Step 2: 2x – 7 = 3

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5 0

3 years ago

4/5 + 3/4 =

marshall27 [118]

The topics you should learn are equating denominators and fractions. This is summing up simple fractions.

So we have to make denominators' numbers the same in order to sum up them all (we can sum fractions if the denominators are the same) , and we did it by cross product (that thing on the picture)

Equating by lcm (least common multiple) is the easiest way, because you might see bigger numbers on other questions, and cross product will bring much bigger numbers, so this technic might confuse you.

By the way lcm of 4 and 5 is already 20

Hope it helps!