Lets take a look at the options first.
option 1 and option 4 are not possible as (8x) (8x) would give us 64x^2, which is not what we want.
we’re left with option 2 & 3. when expanded, option 2 will look like :
16x^2 - 40x - 10x + 25
= 16x^2 - 50x + 25
however, we do not want the 50x. so the answer is option 3, (4x-5) (4x+5)
if you don’t want to find the answer using expanding, there is also another method of expanding.
(a+b)^2 = a^2 - b^2
in this case, 16x^2 will be a^2 and 25 will be b^2. not sure whether you’ve learn this but yea.
If she studied for 2.3 she would have a total of 11.5 because if she got 5 points per hour you just have to multiply it the number of hours she spent studying. So 2.3 x 5 = 11.5! :-)
Answer:
Step-by-step explanation:
Collect like terms
-0.4 - 1 = 0.9x - 0.2x
-1.4 = 0.7x
Divide both sides by 0.7
X = - 2
Answer:
-6.4z -3.5xz
Step-by-step explanation:
