the horizontal distance ( x direction) from A to C is 7 units and
the vertical distance ( y direction) is 5 units
Applying Pythagoras' Theorem to the right triangle
AC² = 7² + 5² = 49 + 25 = 74, hence
AC = = 8.6 units ( to 1 dec. place )
Step 1:
4y + x = 15
−9x + 5y = 20
Step 2: correct
4y + x = 15
x = 15 − 4y
Step 3: wrong
4y + x = 15
4y + (15 − 4y) = 15 wrong step
4y + 15 − 4y = 15
15 = 15
***once you have solved for a variable in one equation, you substitute it in the other equation
Corrected Step 3:
−9x + 5y = 20
-9(15 - 4y) + 5y= 20
(-9*15) + (-9*-4y) + 5y= 20
-135 + 36y + 5y= 20
-135 + 41y= 20
add 135 to both sides
41y= 155
divide both sides by 41
y= 155/41 or 3 32/41 or 3.78
ANSWER: The x value in step 2 should have been substituted in the opposite equation in step 3. The y solution would then be 155/41 or 3 32/41 or 3.78
Hope this helps! :) Would love to be marked brainliest.
Answer:
Step-by-step explanation: